Adaptive environment indoor positioning method and system

Abstract

The application relates to an indoor positioning method and system which is adaptive to an environment. The method comprises the following steps: establishing an indoor positioning measurement model to calculate a preliminary coordinate of a device; establishing an indoor environment error model to correct a preliminary observation distance; establishing a wireless base station optimization model to select a target wireless communication base station; determining a target device preliminary coordinate of a handheld terminal device to the target wireless communication base station, correcting a target preliminary observation distance through the indoor environment error model, and calculating a target coordinate of the handheld terminal device based on the indoor positioning measurement model according to the corrected target observation distance. Since the indoor environment error model is arranged, the preliminary observation distance can be corrected, and the positioning precision of the handheld terminal device can be improved. Through the establishment of the wireless base station optimization model, the base station which is affected by factors such as multipath interference and has poor signal quality can be eliminated, so that the real-time positioning is ensured, and the indoor positioning precision can be improved.

Description

Technical Field

[0001] This invention relates to the field of indoor positioning technology, and in particular to an adaptive indoor positioning method and system. Background Technology

[0002] With the rapid development of 5G and IoT technologies, people's production and living scenarios are gradually changing, placing new demands on the acquisition of indoor location information and positioning accuracy. This has driven the rapid development of location-based service technologies and industries from outdoor to indoor environments. In outdoor environments, Global Navigation Satellite Systems (GNSS) have been widely used with the development of smartphones, and their positioning accuracy is sufficient to meet the needs of relevant fields for location-based services. However, in many scenarios such as indoors, underground, and urban areas with numerous high-rise buildings, GNSS positioning performance deteriorates significantly due to the obstruction of satellite signals by building walls, making it impossible to effectively provide accurate location services to indoor users.

[0003] Traditional indoor positioning methods primarily include communication between densely distributed indoor Wi-Fi devices and mobile phones, and positioning of terminals using carrier wireless communication base stations. The latter method, based on communication between densely distributed indoor Wi-Fi devices and mobile phones, faces significant uncertainties regarding the frequency bands of Wi-Fi signals, limited coverage, user wariness of connecting to unfamiliar Wi-Fi devices, and the potential for investment recovery. The carrier wireless communication base station method measures physical indicators such as radio signal strength, propagation time, and angle of arrival, converting these into distance and angle information between the terminal and the base station. Finally, positioning algorithms convert this distance and angle information into coordinate information for the terminal (including mobile phones, smartwatches, tablets, etc.). However, the electromagnetic environment of communication base stations is more complex indoors than outdoors. Radio signals are reflected multiple times by walls, and refracted and absorbed by indoor objects. These physical factors introduce noise into the distance and angle measurements obtained by the communication base station.

[0004] Therefore, traditional indoor positioning methods often suffer from low accuracy due to the susceptibility of frequency bands to interference, limited coverage, and noise in the collected information. Summary of the Invention

[0005] Therefore, in order to solve the above-mentioned technical problems, an adaptive indoor positioning method and system are provided, which can improve the accuracy of indoor positioning.

[0006] An adaptive indoor positioning method, the method comprising:

[0007] Based on the base station signals transmitted by each wireless communication base station collected by the handheld terminal device, the base station coordinates of each wireless communication base station are found based on the base station signals, the preliminary observation distance from the handheld terminal device to each wireless communication base station is obtained, an indoor positioning measurement model is established, and the preliminary coordinates of the handheld terminal device are calculated based on the indoor positioning measurement model.

[0008] An indoor environmental error model is established based on the base station coordinates and the preliminary coordinates of the device, and the preliminary observation distance is corrected according to the indoor environmental error model.

[0009] A wireless base station optimization model is established based on the corrected preliminary observation distance, and a target wireless communication base station is selected from each of the wireless communication base stations according to the wireless base station optimization model;

[0010] The initial target observation distance from the handheld terminal device to the target wireless communication base station is determined, and the initial target observation distance is corrected by the indoor environment error model to obtain the target observation distance. Based on the target observation distance and the indoor positioning measurement model, the target coordinates of the handheld terminal device are calculated.

[0011] In one embodiment, based on the base station signals transmitted by each wireless communication base station collected by the handheld terminal device, the base station coordinates of each wireless communication base station are found based on the base station signals to obtain the preliminary observation distance from the handheld terminal device to each wireless communication base station, an indoor positioning measurement model is established, and the preliminary coordinates of the handheld terminal device are calculated based on the indoor positioning measurement model, including:

[0012] Based on the base station signal, define the clock error, interference noise level, and equivalent distance error for each of the wireless communication base stations;

[0013] The positioning observation equations for determining the preliminary observation distance are based on the clock error, interference noise, and equivalent distance error.

[0014] The positioning and observation equations are linearized, and the least squares method is used to solve the linearized positioning and observation equations to obtain the correction matrix.

[0015] The initial coordinates of the handheld terminal device are calculated based on the correction matrix.

[0016] In one embodiment, the method further includes:

[0017] Determine the historical location information of the handheld terminal device at the previous moment, and determine the change in location of the handheld terminal device at the current moment;

[0018] Based on the historical location information and the location change amount, the current location of the handheld terminal device is defined.

[0019] In one embodiment, the method further includes:

[0020] Based on the base station signal, the TOA measurement value from the handheld terminal device to each wireless communication base station is determined, and the current indoor propagation environment coefficient and noise interference coefficient are calculated based on the TOA measurement value.

[0021] In one embodiment, an indoor environment error model is established based on the base station coordinates and the preliminary device coordinates, and the preliminary observation distance is corrected according to the indoor environment error model, including:

[0022] The distance parameters from the handheld terminal device to each wireless communication base station are calculated based on the base station coordinates and the preliminary coordinates of the device.

[0023] Based on the distance parameters, the indoor propagation environment coefficient, and the noise interference coefficient, an indoor environmental error model is established, and the preliminary observation distance is corrected based on the indoor environmental error model.

[0024] In one embodiment, a wireless base station optimization model is established based on the corrected preliminary observation distance, and a target wireless communication base station is selected from each of the wireless communication base stations according to the wireless base station optimization model, including:

[0025] The pole base station was determined based on the corrected preliminary observation distance;

[0026] A polar coordinate system is established based on the polar base station, the three-dimensional coordinates of each wireless communication base station are converted into polar coordinates, and the polar angle of each wireless communication base station is determined according to the polar coordinates.

[0027] The target wireless communication base station is selected from each of the wireless communication base stations according to the polar angle.

[0028] In one embodiment, selecting a target wireless communication base station from among the various wireless communication base stations based on the polar angle includes:

[0029] The base station with the smallest polar angle is selected as the first target wireless communication base station;

[0030] Choose the base station with the smallest polar length from the two wireless communication base stations whose polar angle is closest to the first angle, and use it as the second target wireless communication base station.

[0031] Choose the base station with the smallest polar length from the two wireless communication base stations whose polar angle is closest to the second angle, and use it as the third target wireless communication base station.

[0032] The base station with the largest polar angle is designated as the fourth target wireless communication base station.

[0033] An adaptive indoor positioning system, applied to an adaptive indoor positioning method, the system comprising:

[0034] A handheld terminal device is used to collect base station signals transmitted by various wireless communication base stations, find the base station coordinates of each wireless communication base station based on the base station signals, obtain the preliminary observation distance from the handheld terminal device to each wireless communication base station, establish an indoor positioning measurement model, and calculate the preliminary coordinates of the handheld terminal device based on the indoor positioning measurement model.

[0035] Each of the aforementioned wireless communication base stations is used to send the base station signal to the handheld terminal device;

[0036] The handheld terminal device is also used to establish an indoor environment error model based on the base station coordinates and the device's preliminary coordinates, and to correct the preliminary observation distance according to the indoor environment error model;

[0037] The handheld terminal device is also used to establish a wireless base station optimization model based on the corrected preliminary observation distance, and to select a target wireless communication base station from each of the wireless communication base stations based on the wireless base station optimization model.

[0038] The handheld terminal device is further configured to determine the initial target observation distance from the handheld terminal device to the target wireless communication base station, correct the initial target observation distance using the indoor environment error model to obtain the target observation distance, and calculate the target coordinates of the handheld terminal device based on the target observation distance and the indoor positioning measurement model.

[0039] The aforementioned adaptive indoor positioning method and system, by setting an indoor environment error model, can correct the initial observation distance and improve the positioning accuracy of handheld terminal devices. By establishing a wireless base station optimization model, it can quickly select relatively evenly distributed base stations indoors and eliminate base stations that may be affected by multipath interference and other factors that result in poor signal quality. This significantly reduces the complexity and computational load of the method, thereby ensuring the real-time positioning. Moreover, it can use as few base stations as possible to achieve accurate positioning of handheld terminal devices among a large number of base stations. The algorithm has a fast convergence speed and strong anti-interference ability, which can improve the accuracy of indoor positioning. Attached Figure Description

[0040] Figure 1 This is an application environment diagram of an adaptive environment indoor positioning method and a schematic diagram of an adaptive environment indoor positioning system in one embodiment.

[0041] Figure 2This is a flowchart illustrating an indoor positioning method for adaptive environments in one embodiment.

[0042] Figure 3 This is an internal structural diagram of a handheld terminal device in one embodiment. Detailed Implementation

[0043] 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.

[0044] It is understood that the terms "first," "second," etc., used in this application may be used herein to describe target wireless communication base stations, but these target wireless communication base stations are not limited by these terms. These terms are only used to distinguish the first target wireless communication base station from the other target wireless communication base station. For example, without departing from the scope of this application, the first target wireless communication base station may be referred to as the second target wireless communication base station, and similarly, the second target wireless communication base station may be referred to as the first target wireless communication base station. Both the first target wireless communication base station and the second target wireless communication base station are target wireless communication base stations, but they are not the same target wireless communication base station.

[0045] The adaptive indoor positioning method provided in this application can be applied to, for example, environments such as... Figure 1 The application environment shown. For example... Figure 1As shown, the application environment includes a handheld terminal device 110 and several wireless communication base stations 120. The handheld terminal device 110 is connected and communicates with the several wireless communication base stations 120. Based on the base station signals transmitted by each wireless communication base station 120 collected by the handheld terminal device 110, the base station coordinates of each wireless communication base station 120 are found based on the base station signals, and the preliminary observation distance from the handheld terminal device 110 to each wireless communication base station 120 is obtained. An indoor positioning measurement model is established, and the preliminary coordinates of the handheld terminal device 110 are calculated based on the indoor positioning measurement model. An indoor environmental error model is established based on the base station coordinates and the preliminary coordinates of the device, and the preliminary observation distance is corrected based on the indoor environmental error model. A wireless base station optimization model is established based on the corrected preliminary observation distance, and a target wireless communication base station is selected from each wireless communication base station 120 based on the wireless base station optimization model. The target preliminary observation distance from the handheld terminal device 110 to the target wireless communication base station is determined, and the target preliminary observation distance is corrected through the indoor environmental error model to obtain the target observation distance. The target coordinates of the handheld terminal device 110 are calculated based on the target observation distance and the indoor positioning measurement model. Among them, the handheld terminal device 110 may be, but is not limited to, various personal computers, laptops, smartphones, robots, unmanned aerial vehicles, tablets, locators and portable wearable devices, etc.

[0046] In one embodiment, such as Figure 2 As shown, an adaptive indoor positioning method is provided, including the following steps:

[0047] Step 202: Based on the base station signals transmitted by each wireless communication base station, the base station coordinates of each wireless communication base station are found based on the base station signals, the preliminary observation distance from the handheld terminal device to each wireless communication base station is obtained, an indoor positioning measurement model is established, and the preliminary coordinates of the handheld terminal device are calculated based on the indoor positioning measurement model.

[0048] Indoor handheld terminal devices can communicate with various wireless communication base stations and receive base station signals transmitted by each station. In an indoor environment, based on the initial observed distances from the handheld terminal device to each wireless communication base station, a positioning measurement model can be established, and the least squares method can be used to initially calculate the current position coordinates (x, y) of the handheld terminal device. t ,y t ,z t ).

[0049] Specifically, in one embodiment, an adaptive indoor positioning method further includes: defining clock bias, interference noise, and equivalent distance error for each wireless communication base station based on base station signals; determining a set of positioning observation equations for preliminary observation distance based on clock bias, interference noise, and equivalent distance error; linearizing the set of positioning observation equations and solving the linearized set of positioning observation equations using the least squares method to obtain a correction matrix; and calculating the preliminary coordinates of the handheld terminal device based on the correction matrix.

[0050] First, we can define the preliminary observation distance from the handheld terminal device to each wireless communication base station, that is, define the observation distance from the handheld terminal device to the wireless communication base station as the "pseudorange". The pseudorange includes the error term due to factors such as the clock asynchrony between the handheld terminal device and the wireless communication base station, propagation delay, and noise interference. That is, the pseudorange measurement value is ρ=r+δt. u +ε, where ρ is the pseudorange measurement from the handheld terminal device to the wireless communication base station, in meters (m); r is the true geometric distance from the handheld terminal device to the wireless communication base station, in meters (m); δt u Let ε be the clock difference caused by the clock asynchrony between the handheld terminal device and the wireless communication base station, and let δt be the interference noise. u ε represents the equivalent distance error, in meters (m).

[0051] In one embodiment, an adaptive indoor positioning method further includes: determining the historical location information of the handheld terminal device at the previous moment, and determining the change in the location of the handheld terminal device at the current moment; and defining the current location of the handheld terminal device based on the historical location information and the change in location.

[0052] Specifically, the position of the handheld terminal device at the previous moment was (x t-1 ,y t-1 ,z t-1 The change in position from the current positioning result is (δx) t ,δy t ,δz t The location of the handheld terminal device to be solved at the current moment is (x). t ,y t ,z t And satisfy the following equation:

[0053]

[0054] Then, for n wireless communication base stations in the indoor environment, the pseudorange positioning observation equations are established as follows:

[0055]

[0056] Where n is the number of wireless communication base stations in the indoor environment; (x1, y1, z1), (x2, y2, z2), ... (x n y n , z n Let ρ1, ρ2, ..., ρn be the location coordinates of n wireless communication base stations. n Let x be the pseudorange measurement (observation distance) from the handheld terminal device to n wireless communication base stations at the current moment; t y t , z t ) represents the current location coordinates of the handheld terminal device.

[0057] In the established pseudorange positioning observation equations, the position coordinates of the wireless communication base station are (x1, y1, z1)(x2, y2, z2), ... (x n y n , z n ( ) represents known information, pseudorange measurements ρ1, ρ2, ..., ρ n The remaining three coordinate components (x, y, y) in the equation system are obtained directly from the handheld terminal device. t y t , z t ) and clock difference δt u The unknowns to be solved are: Theoretically, if a handheld terminal device receives signals from four or more base stations, the unknowns in the equation can be solved, thus enabling real-time positioning of the handheld terminal device.

[0058] Next, we calculate the direction cosines of the n wireless communication base stations relative to the three coordinate axes, that is, the direction cosine of the i-th wireless communication base station is:

[0059]

[0060] Among them, u i v i w i These are the position coordinates (x, y) of the handheld terminal device at the previous moment. t-1 y t-1 , z t-1 The coordinates of the location (x) of the i-th wireless communication base station i y i , z i The direction cosines of the x-axis, y-axis, and z-axis in a rectangular coordinate system.

[0061] Next, the pseudorange positioning observation equations are linearized, and the results are converted into matrix form:

[0062]

[0063] Where R1, R2, ..., Rn The positions (x, x) of the n wireless communication base stations to the handheld terminal device at the previous time are respectively. t-1 y t-1 , z t-1 The distance.

[0064] Let the observation coefficient matrix Correction matrix

[0065] matrix Among them, δx in the correction matrix ΔX t ,δy t , δz t ,δt u The four unknown parameters to be solved represent the displacement of the handheld terminal device in the Cartesian coordinate system at the current moment along the x-axis, y-axis, and z-axis, as well as the clock error of the handheld terminal device.

[0066] The pseudorange positioning observation equations are linearized and expressed as: A·ΔX=B, where there are four unknown parameters δx to be solved. t ,δy t , δz t ,δt u At the current moment, the number of wireless communication base stations in the indoor environment is far greater than 4. Since the number of observation equations is greater than the number of parameters to be determined, the least squares method can be used to solve the linearized pseudorange positioning observation equations, and the correction matrix ΔX is obtained as: ΔX=(A T ·A) -1 ·A T ·B, where A T Let A represent the transpose of matrix A, (A T ·A) -1 Representation matrix (A) T The inverse of A).

[0067] After calculating the correction matrix ΔX using the least squares method, we can initially obtain the position coordinates of the handheld terminal device in the Cartesian coordinate system at the current moment: The initial position coordinates of the handheld terminal device can be freely set and substituted into the above calculation process. For example, the origin of the coordinate system can be chosen, such as: Where (x0, y0, z0) are the position coordinates of the handheld terminal device at the initial moment.

[0068] Step 204: Establish an indoor environmental error model based on the base station coordinates and the preliminary equipment coordinates, and correct the preliminary observation distance according to the indoor environmental error model.

[0069] For different indoor propagation environments, an indoor environment error model can be established based on the known accurate base station coordinates and the preliminary calculated device coordinates. This indoor environment error model can then be used to correct the preliminary observation distance between the handheld terminal device and the wireless communication base station obtained in this indoor environment.

[0070] Specifically, in one embodiment, an adaptive indoor positioning method may further include: determining the TOA measurement value from the handheld terminal device to each wireless communication base station based on the base station signal, and calculating the current indoor propagation environment coefficient and noise interference coefficient based on the TOA measurement value.

[0071] In one embodiment, the handheld terminal device can also calculate the distance parameters from the handheld terminal device to each wireless communication base station based on the base station coordinates and the device's preliminary coordinates; based on the distance parameters, indoor propagation environment coefficient, and noise interference coefficient, an indoor environment error model is established, and the preliminary observation distance is corrected based on the indoor environment error model.

[0072] Firstly, considering the complexity and variability of indoor environments, the TOA measurement data from the handheld terminal device to the wireless communication base station includes error terms due to factors such as signal propagation environment, clock asynchrony, propagation delay, and noise interference. Therefore, the TOA measurement value obtained by the handheld terminal device is: t ρ =γ0·t r +t u +t ε , where t ρ γ0 is the TOA measurement value from the handheld terminal device to the wireless communication base station, γ0 is the indoor propagation environment coefficient, and t0 is the distance to the wireless communication base station. r Let t be the TOA value from the handheld terminal device to the wireless communication base station under ideal conditions. u The delay caused by clock asynchrony between the handheld terminal device and the wireless communication base station, t ε Errors caused by noise interference.

[0073] Next, t can be used ρ =γ0·t r +t u -t ε Divide both sides by t r ,get: Next, multiply the time by the speed of light c, in meters (m), to get: Therefore, we get: Where ρ is the pseudorange measurement value from the handheld terminal device to the wireless communication base station, in meters (m), and r is the actual geometric distance from the handheld terminal device to the wireless communication base station, in meters (m). Through a large amount of experimental data, it is known that in a certain indoor propagation environment, γ0 and η are basically close to a constant value. Therefore, in different indoor environments, γ0 and η in the current indoor environment can be calculated by using the actual geometric distances r1 and r2 from the handheld terminal device to the wireless communication base station obtained in advance, as well as the pseudorange measurement values ​​ρ1 and ρ2 from the handheld terminal device to the wireless communication base station.

[0074] Furthermore, the indoor environmental error model is established as follows: Where γ is the indoor environmental error coefficient, γ0 is the indoor propagation environment coefficient, η is the indoor noise interference coefficient, and r is the distance from the handheld terminal device to the wireless communication base station. Since r is a value much smaller than γ0, it can be replaced by the distance d from the handheld terminal device's location coordinates to the wireless communication base station, as initially calculated. Thus, the model can be simplified to:

[0075] Step 206: Establish a wireless base station optimization model based on the corrected preliminary observation distance, and select a target wireless communication base station from each wireless communication base station based on the wireless base station optimization model.

[0076] In the indoor environment where the handheld terminal device is located, a wireless base station optimization model can be established to select the four best base stations from multiple wireless communication base stations for secondary precise positioning of the handheld terminal device.

[0077] Specifically, in one embodiment, an adaptive indoor positioning method may further include determining a pole base station based on a corrected preliminary observation distance; establishing a polar coordinate system based on the pole base station, converting the three-dimensional coordinates of each wireless communication base station into polar coordinates, and determining the polar angle of each wireless communication base station based on the polar coordinates; and selecting a target wireless communication base station from among the wireless communication base stations based on the polar angle.

[0078] In theory, 3D positioning of a handheld terminal device requires at least four base stations for calculation, and these four base stations should ideally be evenly distributed around the handheld terminal device. Therefore, the base station with the smallest pseudorange from the handheld terminal device is selected as the pole base station, and a polar coordinate system is established with the pole base station as the pole and the x-axis as the polar axis. The 3D coordinates of all base stations (ignoring the z-coordinate) are converted to polar coordinates, and then the polar angles of all base stations after conversion are sorted in ascending order, as follows:

[0079]

[0080]

[0081] In one embodiment, an adaptive indoor positioning method may further include selecting the base station with the smallest polar angle as the first target wireless communication base station; selecting the base station with the smallest polar length from the two wireless communication base stations whose polar angles are closest to the first angle as the second target wireless communication base station; selecting the base station with the smallest polar length from the two wireless communication base stations whose polar angles are closest to the second angle as the third target wireless communication base station; and selecting the base station with the largest polar angle as the fourth target wireless communication base station.

[0082] If the polar angle θ n -θ1≥315° indicates that base station k1 and k n If the base stations are close in direction, the base station k1 with the smallest polar angle is first selected as the first target wireless communication base station and numbered G1. Then, the base station with the smaller polar length among the two base stations with polar angles closest to (θ1+90°) is selected as the second target wireless communication base station and numbered G2. Next, the base station with the smaller polar length among the two base stations with polar angles closest to (θ1+180°) is selected as the third target wireless communication base station and numbered G3. Finally, the base station with the smaller polar length among the two base stations with polar angles closest to (θ1+270°) is selected as the fourth target wireless communication base station and numbered G4. Thus, G1, G2, G3, and G4 are the four base stations that are finally selected to participate in the positioning calculation.

[0083] If the polar angle θ n -θ1 < 315°, indicating that base station k1 and k n If the directional distances are relatively large, the base station k1 with the smallest polar angle is first selected as the first target wireless communication base station, and it is numbered G1. Then, the base station with the polar angle closest to the target base station is selected. Of the two base stations, the one with the smaller extreme length is selected as the second target wireless communication base station and numbered G2. Then, the base station with the polar angle closest to... Among the two base stations, the base station with the smaller polar angle is selected as the third target wireless communication base station and numbered G3. Finally, the base station k1 with the largest polar angle is selected as the fourth target wireless communication base station and numbered G4. Then, G1, G2, G3, and G4 are the four base stations that are finally selected to participate in the positioning calculation.

[0084] Step 208: Determine the initial target observation distance from the handheld terminal device to the target wireless communication base station, correct the initial target observation distance using an indoor environmental error model to obtain the target observation distance, and calculate the target coordinates of the handheld terminal device based on the target observation distance using an indoor positioning measurement model.

[0085] A high-precision positioning calculation model can be established on the handheld terminal device. Specifically, when using the high-precision positioning calculation model for calculation, based on the established indoor positioning measurement model, the TOA measurement data obtained by the handheld terminal device is used to initially calculate the current position coordinates (x, y) of the handheld terminal device. t y t , z t Then, based on the established wireless base station optimization model, the four optimal base stations G1, G2, G3, and G4 are selected from multiple wireless communication base stations in the indoor environment. The pseudorange measurement values ​​from the handheld terminal device to these four base stations are... Next, based on the established indoor environment error model, the pseudorange measurements from the handheld terminal device to these four base stations were corrected. The corrected pseudorange values ​​are as follows: Finally, the corrected pseudorange measurements from the handheld terminal to the four base stations were used. The coordinates of the handheld terminal device are recalculated using the established indoor positioning measurement model, resulting in a second, more precise positioning calculation. This calculation determines the precise coordinates of the handheld terminal device at the current moment. At the next moment, the high-precision positioning model can be reused to obtain the position coordinates of the handheld terminal device at that moment.

[0086] It should be understood that although the steps in the flowchart above are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowchart above 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 performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.

[0087] In one embodiment, such as Figure 1 As shown, an adaptive indoor positioning system is provided, including: a handheld terminal device 110, used to collect base station signals transmitted by each wireless communication base station 120, find the base station coordinates of each wireless communication base station 120 based on the base station signals, obtain the preliminary observation distance from the handheld terminal device 110 to each wireless communication base station 120, establish an indoor positioning measurement model, and calculate the preliminary device coordinates of the handheld terminal device 110 based on the indoor positioning measurement model.

[0088] Each wireless communication base station 120 is used to send base station signals to the handheld terminal device 110;

[0089] The handheld terminal device 110 is also used to establish an indoor environmental error model based on the base station coordinates and the device's preliminary coordinates, and to correct the preliminary observation distance based on the indoor environmental error model;

[0090] The handheld terminal device 110 is also used to establish a wireless base station optimization model based on the corrected preliminary observation distance, and to select a target wireless communication base station 120 from each wireless communication base station 120 according to the wireless base station optimization model;

[0091] The handheld terminal device 110 is also used to determine the initial observation distance of the handheld terminal device 110 to the target wireless communication base station, correct the initial observation distance of the target through an indoor environmental error model, obtain the target observation distance, and calculate the target coordinates of the handheld terminal device 110 based on the target observation distance and an indoor positioning measurement model.

[0092] In one embodiment, the handheld terminal device 110 is further configured to define the clock bias, interference noise level, and equivalent distance error corresponding to each wireless communication base station 120 based on the base station signal; determine a set of positioning observation equations for the preliminary observation distance based on the clock bias, interference noise level, and equivalent distance error; linearize the set of positioning observation equations and solve the linearized set of positioning observation equations using the least squares method to obtain a correction matrix; and calculate the preliminary coordinates of the handheld terminal device 110 based on the correction matrix.

[0093] In one embodiment, the handheld terminal device 110 is further configured to determine the historical location information of the handheld terminal device 110 at the previous moment, and determine the change in the location of the handheld terminal device 110 at the current moment; and define the current location of the handheld terminal device 110 based on the historical location information and the change in location.

[0094] In one embodiment, the handheld terminal device 110 is further configured to determine the TOA measurement value from the handheld terminal device 110 to each wireless communication base station 120 based on the base station signal, and calculate the current indoor propagation environment coefficient and noise interference coefficient based on the TOA measurement value.

[0095] In one embodiment, the handheld terminal device 110 is further configured to calculate the distance parameters from the handheld terminal device 110 to each wireless communication base station 120 based on the base station coordinates and the device's preliminary coordinates; establish an indoor environment error model based on the distance parameters, indoor propagation environment coefficient, and noise interference coefficient; and correct the preliminary observation distance based on the indoor environment error model.

[0096] In one embodiment, the handheld terminal device 110 is further configured to determine the pole base station based on the corrected preliminary observation distance; establish a polar coordinate system based on the pole base station, convert the three-dimensional coordinates of each wireless communication base station 120 into polar coordinates, and determine the polar angle of each wireless communication base station 120 based on the polar coordinates; and select the target wireless communication base station from each wireless communication base station 120 based on the polar angle.

[0097] In one embodiment, the handheld terminal device 110 is further configured to: select the base station with the smallest polar angle as the first target wireless communication base station; select the base station with the smallest polar length among the two wireless communication base stations whose polar angle is closest to the first angle as the second target wireless communication base station; select the base station with the smallest polar length among the two wireless communication base stations whose polar angle is closest to the second angle as the third target wireless communication base station; and select the base station with the largest polar angle as the fourth target wireless communication base station.

[0098] In one embodiment, a handheld terminal device is provided, the internal structure of which can be shown in the following diagram. Figure 3 As shown, the handheld terminal device includes a processor, memory, network interface, display screen, and input device connected via a system bus. The processor provides computing and control capabilities. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage medium. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it implements an adaptive indoor positioning method. The display screen can be an LCD screen or an e-ink screen. The input device can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the device's casing, or an external keyboard, touchpad, or mouse.

[0099] Those skilled in the art will understand that Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the solution of this application and does not constitute a limitation on the handheld terminal device to which the solution of this application is applied. A specific handheld terminal device may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0100] In one embodiment, a handheld terminal device is provided, including a memory and a processor, the memory storing a computer program, the processor executing the computer program to implement steps of an adaptive indoor positioning method.

[0101] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, the computer program being executed by a processor to implement the steps of an indoor positioning method adapted to the environment.

[0102] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0103] 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.

[0104] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. An adaptive indoor positioning method, characterized in that, The method includes: Based on the base station signals transmitted by each wireless communication base station collected by the handheld terminal device, the base station coordinates of each wireless communication base station are found based on the base station signals, the preliminary observation distance from the handheld terminal device to each wireless communication base station is obtained, an indoor positioning measurement model is established, and the preliminary coordinates of the handheld terminal device are calculated based on the indoor positioning measurement model. An indoor environmental error model is established based on the base station coordinates and the preliminary coordinates of the device, and the preliminary observation distance is corrected according to the indoor environmental error model. This includes: calculating the distance parameters from the handheld terminal device to each wireless communication base station based on the base station coordinates and the preliminary coordinates of the device; establishing an indoor environmental error model based on the distance parameters, indoor propagation environment coefficient, and noise interference coefficient; and correcting the preliminary observation distance according to the indoor environmental error model. A wireless base station optimization model is established based on the corrected preliminary observation distance, and a target wireless communication base station is selected from each of the wireless communication base stations according to the wireless base station optimization model. This includes: determining pole base stations based on the corrected preliminary observation distance; establishing a polar coordinate system based on the pole base stations, converting the three-dimensional coordinates of each wireless communication base station to polar coordinates, and determining the polar angle of each wireless communication base station according to the polar coordinates; selecting a target wireless communication base station from each of the wireless communication base stations according to the polar angle, including: selecting the base station with the smallest polar angle as the first target wireless communication base station; selecting the base station with the smallest polar length from the two wireless communication base stations whose polar angles are closest to the first angle as the second target wireless communication base station; the first angle is the polar angle of the first target wireless communication base station + 90°; selecting the base station with the smallest polar length from the two wireless communication base stations whose polar angles are closest to the second angle as the third target wireless communication base station; the second angle is the polar angle of the first target wireless communication base station + 180°; and selecting the base station with the largest polar angle as the fourth target wireless communication base station. The initial target observation distance from the handheld terminal device to the target wireless communication base station is determined, and the initial target observation distance is corrected by the indoor environment error model to obtain the target observation distance. Based on the target observation distance and the indoor positioning measurement model, the target coordinates of the handheld terminal device are calculated.

2. The adaptive environment indoor positioning method according to claim 1, characterized in that, The process involves collecting base station signals transmitted by various wireless communication base stations using a handheld terminal device, finding the base station coordinates of each wireless communication base station based on the base station signals, obtaining the preliminary observation distance from the handheld terminal device to each wireless communication base station, establishing an indoor positioning measurement model, and calculating the preliminary coordinates of the handheld terminal device based on the indoor positioning measurement model. This includes: Based on the base station signal, define the clock error, interference noise level, and equivalent distance error for each of the wireless communication base stations; The positioning observation equations for determining the preliminary observation distance are based on the clock error, interference noise, and equivalent distance error. The positioning and observation equations are linearized, and the least squares method is used to solve the linearized positioning and observation equations to obtain the correction matrix. The initial coordinates of the handheld terminal device are calculated based on the correction matrix.

3. The adaptive environment indoor positioning method according to claim 2, characterized in that, The method further includes: Determine the historical location information of the handheld terminal device at the previous moment, and determine the change in location of the handheld terminal device at the current moment; Based on the historical location information and the location change amount, the current location of the handheld terminal device is defined.

4. The adaptive environment indoor positioning method according to claim 1, characterized in that, The method further includes: Based on the base station signal, the TOA measurement value from the handheld terminal device to each wireless communication base station is determined, and the current indoor propagation environment coefficient and noise interference coefficient are calculated based on the TOA measurement value.

5. An adaptive indoor positioning system, applied to the adaptive indoor positioning method as described in any one of claims 1 to 3, characterized in that, The system includes: A handheld terminal device is used to collect base station signals transmitted by various wireless communication base stations, find the base station coordinates of each wireless communication base station based on the base station signals, obtain the preliminary observation distance from the handheld terminal device to each wireless communication base station, establish an indoor positioning measurement model, and calculate the preliminary coordinates of the handheld terminal device based on the indoor positioning measurement model. Each of the aforementioned wireless communication base stations is used to send the base station signal to the handheld terminal device; The handheld terminal device is further configured to establish an indoor environment error model based on the base station coordinates and the device's preliminary coordinates, and to correct the preliminary observation distance according to the indoor environment error model, including: calculating the distance parameters from the handheld terminal device to each wireless communication base station based on the base station coordinates and the device's preliminary coordinates; establishing an indoor environment error model based on the distance parameters, indoor propagation environment coefficient, and noise interference coefficient, and correcting the preliminary observation distance according to the indoor environment error model; The handheld terminal device is further configured to establish a wireless base station optimization model based on the corrected preliminary observation distance, and select a target wireless communication base station from each of the wireless communication base stations according to the wireless base station optimization model, including: determining a pole base station based on the corrected preliminary observation distance; establishing a polar coordinate system based on the pole base station, converting the three-dimensional coordinates of each wireless communication base station into polar coordinates, and determining the polar angle of each wireless communication base station according to the polar coordinates; selecting a target wireless communication base station from each of the wireless communication base stations according to the polar angle, including: selecting the base station with the smallest polar angle as the first target wireless communication base station; selecting the base station with the smallest polar length from the two wireless communication base stations whose polar angle is closest to the first angle as the second target wireless communication base station; the first angle is the polar angle of the first target wireless communication base station + 90°; selecting the base station with the smallest polar length from the two wireless communication base stations whose polar angle is closest to the second angle as the third target wireless communication base station; the second angle is the polar angle of the first target wireless communication base station + 180°; and selecting the base station with the largest polar angle as the fourth target wireless communication base station. The handheld terminal device is further configured to determine the initial target observation distance from the handheld terminal device to the target wireless communication base station, correct the initial target observation distance using the indoor environment error model to obtain the target observation distance, and calculate the target coordinates of the handheld terminal device based on the target observation distance and the indoor positioning measurement model.

6. The adaptive indoor positioning system according to claim 5, characterized in that, The handheld terminal device is further configured to define, based on the base station signal, the clock bias, interference noise level, and equivalent distance error corresponding to each of the wireless communication base stations; determine the positioning observation equation set for the preliminary observation distance based on the clock bias, interference noise level, and equivalent distance error; linearize the positioning observation equation set and solve the linearized positioning observation equation set using the least squares method to obtain a correction matrix; and calculate the preliminary device coordinates of the handheld terminal device based on the correction matrix.

7. The adaptive indoor positioning system according to claim 6, characterized in that, The handheld terminal device is further configured to determine the historical location information of the handheld terminal device at the previous moment, and to determine the change in the location of the handheld terminal device at the current moment. Based on the historical location information and the location change amount, the current location of the handheld terminal device is defined.

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