Parking lot vehicle positioning method, device and medium based on signal source

Abstract

The application discloses a parking lot vehicle positioning method and device based on a signal source, a terminal device collects wireless signals emitted by signal sources in the surrounding environment and measures the signal strength, a direct prediction position is obtained through a fingerprint matching method, an operation prediction position is calculated through a multi-signal source weighted solution method from the direct prediction position, and the operation prediction position and the last positioning position are obtained through a weighted method to obtain a current positioning position; the stability of the fingerprint matching method is ensured, the positioning response speed is improved through the multi-signal source weighted solution method, the positioning accuracy is ensured, the requirement of high refresh rate of vehicle positioning navigation when the vehicle speed is high can be met, and the overall positioning efficiency is improved; further, signal sources meeting the conditions are screened according to different situations to participate in the calculation of the operation prediction position, effective signal sources are dynamically and timely screened, and the calculation of the operation prediction position and the final positioning position is more accurate.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of surveying and navigation, in particular to a parking lot vehicle positioning method based on signal sources, equipment and medium. BACKGROUND

[0002] The existing parking lot vehicle positioning technology is usually based on the Bluetooth signal broadcasted by the Bluetooth ibeacon beacon. This method needs to arrange Bluetooth beacons in the parking lot and deploy a calculation software in the cloud. The RSSI (Received Signal Strength Indication) of the Bluetooth signal is collected by the user's mobile phone and transmitted to the calculation software. The calculation software calculates the vehicle position and transmits it to the mobile phone.

[0003] However, in actual use, the vehicle speed in the parking lot is relatively fast, and the efficiency of the existing vehicle positioning method is low. SUMMARY

[0004] The main purpose of the present application is to provide a parking lot vehicle positioning method based on signal sources, equipment and medium, which aims to solve the technical problem of low efficiency of the existing vehicle positioning method.

[0005] To achieve the above purpose, the present application provides a parking lot vehicle positioning method based on signal sources, which is used for a terminal device, the terminal device is located in a target vehicle, and comprises:

[0006] Receiving the wireless signal emitted by the plurality of signal sources arranged in the parking lot to obtain a signal strength set;

[0007] According to the signal strength set, a direct prediction position of the target vehicle is obtained by using a fingerprint matching positioning method;

[0008] According to the direct prediction position, an operation prediction position of the target vehicle is obtained by using a multi-signal source weighted calculation method;

[0009] According to the operation prediction position, the positioning position of the target vehicle is obtained.

[0010] Optionally, the step of obtaining the operation prediction position of the target vehicle according to the direct prediction position by using the multi-signal source weighted calculation method comprises:

[0011] Judging whether the positioning times are greater than a preset positioning times;

[0012] If yes, the operation prediction position is obtained according to the direct prediction position and the size relationship between the maximum value in the signal strength and the preset threshold value in each positioning.

[0013] Optionally, after the step of judging whether the positioning times is greater than the preset positioning times, the method further comprises:

[0014] If not, the operation predicted position is determined as the direct predicted position.

[0015] Optionally, the preset threshold is Rss1, and Rss1 represents the signal strength of the signal source measured by the terminal device at the standard distance position from the signal source.

[0016] If yes, the operation predicted position is obtained according to the direct predicted position and the size relationship between the maximum value in the signal strength in each positioning and the preset threshold.

[0017] If the maximum value in the signal strength is greater than or equal to Rss1, the operation predicted position is determined as the direct predicted position.

[0018] Optionally, the preset threshold is Rss1 and Rss2, Rss1 represents the signal strength of the signal source measured by the terminal device at the standard distance position from the signal source, and Rss2 represents the signal strength of the signal source measured by the terminal device at the 2 times standard distance position from the signal source.

[0019] If yes, the operation predicted position is obtained according to the direct predicted position and the size relationship between the maximum value in the signal strength in each positioning and the preset threshold.

[0020] If the maximum value in the signal strength is greater than or equal to Rss2 and less than Rss1, the operation predicted position is obtained according to the following relationship:

[0021]

[0022]

[0023] wherein (x″ k ,y″ k ) is the coordinate of the operation predicted position in the kth positioning, (x″′ k ,y″′ k ) is the coordinate of the direct predicted position in the kth positioning, r k,min1 , r k,min2 are the minimum value and the second minimum value in the distance corresponding to the signal strength of each signal source, x″ k,min1 , y″ k,min1 are the coordinate values of the signal source corresponding to r k,min1 , x″ k,min2 , y″ k,min2 are the coordinate values of the signal source corresponding to r k,min2 .

[0024] Optionally, the preset threshold values are Rss2 and Rss3, Rss2 represents the signal strength of the signal source measured by the terminal device at a position with a distance of 2 times the standard distance from the signal source, and Rss3 represents the signal strength of the signal source measured by the terminal device at a position with a distance of 3 times the standard distance from the signal source.

[0025] If yes, the step of obtaining the operation predicted position according to the direct predicted position and the size relationship between the maximum value in the signal strength in each positioning and the preset threshold value comprises:

[0026] If the maximum value in the signal strength is greater than or equal to Rss3 and less than Rss2, the operation predicted position is obtained according to the following relationship:

[0027]

[0028]

[0029] wherein (x″ k ,y″ k ) is the coordinate of the operation predicted position in the kth positioning, (x″′ k ,y″′ k ) is the coordinate of the direct predicted position in the kth positioning, r k,min1 , r k,min2 are the minimum value and the second minimum value in the distances corresponding to the signal strengths of the respective signal sources, x″ k,min1 , y″ k,min1 are the coordinate values of the signal source corresponding to r k,min1 , x″ k,min2 , y″ k,min2 are the coordinate values of the signal source corresponding to r k,min2 .

[0030] Optionally, the preset threshold values are Rss3 and Rss4, Rss3 represents the signal strength of the signal source measured by the terminal device at a position with a distance of 3 times the standard distance from the signal source, and Rss4 represents the signal strength of the signal source measured by the terminal device at a position with a distance of 4 times the standard distance from the signal source.

[0031] If yes, the step of obtaining the operation predicted position according to the direct predicted position and the size relationship between the maximum value in the signal strength in each positioning and the preset threshold value comprises:

[0032] If the maximum value in the signal strength is greater than or equal to Rss4 and less than Rss3, the operation predicted position is determined as the direct predicted position, and the weight value is obtained according to the following relationship:

[0033]

[0034] wherein, a is a weight value of the kth positioning, used for calculating the positioning position, (x" k ,y" k ) is a coordinate of the calculated predicted position of the kth positioning, (x′ k-1 ,y′ k-1 ) is a coordinate of the positioning position of the (k-1)th positioning, and d is a standard distance.

[0035] Optionally, the step of obtaining the positioning position of the target traveling vehicle according to the calculated predicted position comprises:

[0036] The positioning position is obtained according to the following relationship:

[0037] (x′ k ,y′ k ) = (x′ k-1 ,y′ k-1 ) + a·(x" k -x′ k ,y" k -y′ k )

[0038] wherein, a is a weight value of the kth positioning, (x′ k-1 ,y′ k-1 ) is a coordinate of the positioning position of the (k-1)th positioning, (x" k ,y" k ) is a coordinate of the calculated predicted position of the kth positioning, and (x′ k ,y′ k ) is a coordinate of the positioning position of the kth positioning.

[0039] In addition, to achieve the above object, the present application also provides a computer device, comprising a memory and a processor, the memory stores a computer program, and the processor executes the computer program to realize the above method.

[0040] In addition, to achieve the above object, the present application also provides a computer readable storage medium, which stores a computer program, and the processor executes the computer program to realize the above method.

[0041] The beneficial effects that can be achieved by the present application.

[0042] The embodiment of the application provides a parking lot vehicle positioning method based on a signal source, a device and a medium, which are used for a terminal device, the terminal device is located in a target running vehicle, wireless signals emitted by a plurality of signal sources arranged in a parking lot are received, and a signal strength set is obtained; according to the signal strength set, a fingerprint matching positioning method is used to obtain a direct prediction position of the target running vehicle; according to the direct prediction position, a multi-signal source weighted solution algorithm is used to obtain a calculation prediction position of the target running vehicle; and according to the calculation prediction position, a positioning position of the target running vehicle is obtained. That is, the terminal device collects wireless signals emitted by signal sources in the surrounding environment and measures the signal strengths of the wireless signals, a direct prediction position is obtained through a fingerprint matching method, a calculation prediction position is obtained through a multi-signal source weighted solution method from the direct prediction position, and the current positioning position is obtained through a weighted method from the calculation prediction position and the last positioning position; the stability of the fingerprint matching method is obtained, the positioning response speed is improved through the multi-signal source weighted solution algorithm, the positioning accuracy is ensured, the requirement of high refresh rate of vehicle positioning navigation when the vehicle speed is high is met, and the overall positioning efficiency is improved. BRIEF DESCRIPTION OF DRAWINGS

[0043] Figure 1 A flowchart of a parking lot vehicle positioning method based on a signal source is provided for the embodiment of the application.

[0044] Figure 2 A signal source distribution diagram of a certain parking lot is provided for the embodiment of the application.

[0045] The implementation, functional features and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0046] It should be understood that the specific embodiments described herein are merely intended to explain the application and are not intended to limit the application.

[0047] The main solution of the embodiment of the application is that a parking lot vehicle positioning method based on a signal source, a device and a medium are provided, which are used for a terminal device, the terminal device is located in a target running vehicle, wireless signals emitted by a plurality of signal sources arranged in a parking lot are received, and a signal strength set is obtained; according to the signal strength set, a fingerprint matching positioning method is used to obtain a direct prediction position of the target running vehicle; according to the direct prediction position, a multi-signal source weighted solution algorithm is used to obtain a calculation prediction position of the target running vehicle; and according to the calculation prediction position, a positioning position of the target running vehicle is obtained.

[0048] In the prior art, the cloud calculation software for vehicle positioning mainly includes the nearest neighbor method and the fingerprint positioning method. The applicant finds that the nearest neighbor method based on Bluetooth positioning only uses the signal of one beacon for positioning, and can achieve high-precision positioning mainly in the position within 3 meters close to the Bluetooth beacon. The positioning accuracy is poor beyond the range. In the application of parking lot vehicle positioning, the jumping is large, the main reason is that the vehicle speed is fast and the roof is shielded, so the conversion distance between the terminal device and the beacon is always greater than 3 meters, and the positioning accuracy cannot meet the requirements of the vehicle lane. The fingerprint positioning method based on Bluetooth ibeacon needs to establish a fingerprint library in advance, and all signal sources are used for positioning. Dozens of beacon signal sources far away from the mobile terminal (about 10 meters) will seriously affect the positioning resolution, and the calculation amount is large. The positioning stability of this method is good, but the positioning response is slow, which can meet the application of walking positioning and navigation, but cannot meet the high refresh rate requirements of vehicle lane positioning and navigation. Especially in the actual use scene, the vehicle speed in the parking lot often exceeds 15Km / h, and the existing method is difficult to meet the requirements of accurate and fast positioning, and the overall positioning efficiency is low.

[0049] Therefore, the present application provides a solution. According to the wireless signals emitted by the signal sources in the surrounding environment collected by the terminal device and the signal strength measured, the direct prediction position is obtained by the fingerprint matching method, and then the operation prediction position is calculated by the multi-signal source weighted solution method from the direct prediction position. The current positioning position is obtained by weighting the operation prediction position and the last positioning position. Both the stability of the fingerprint matching method and the positioning response speed are improved by the multi-signal source weighted solution method, which ensures the accuracy of the positioning and meets the high refresh rate requirements of the vehicle lane positioning and navigation when the vehicle speed is high. It also improves the overall efficiency of the positioning. Further, according to different conditions, the signal sources meeting the conditions are selected to participate in the calculation of the operation prediction position, which dynamically and real-timely selects the effective signal sources, so that the calculation of the operation prediction position and the final positioning position is more accurate.

[0050] Reference Figure 1 The embodiment of the present application provides a parking lot vehicle lane positioning method based on signal sources, which is used for a terminal device located in a target traveling vehicle and comprises the following steps.

[0051] S10: receiving the wireless signals emitted by the multiple signal sources arranged in the parking lot, and obtaining a signal strength set;

[0052] In the specific implementation process, as Figure 2As shown, a signal source, i.e. a Bluetooth beacon, is arranged in the passage of the parking lot. When the vehicle to be positioned travels in the parking lot, the terminal device on the target traveling vehicle receives the wireless signal emitted by the signal source and calculates the positioning position, which can be a mobile terminal such as a mobile phone placed in the vehicle or a vehicle-mounted computer or the like on the vehicle. After obtaining the positioning position, it can be displayed on the terminal device or transmitted to other devices to meet the different needs of the vehicle owner.

[0053] The positioning frequency of the terminal device is This value is also the interval at which the positioning program obtains data from the scanning interface of the terminal device. During the driving of the target traveling vehicle, the terminal device receives multiple wireless signals emitted by the signal sources in multiple positioning processes and measures the signal strength (RSSI) according to these signals to form a signal strength set. The mobile phone will report all the signal strengths of the signal sources (beacons) received in this time period at a fixed frequency.

[0054] The signal strength of the beacon received by the mobile phone for the kth time is as follows:

[0055]

[0056] Wherein, k is the number of times of reporting data from the start of positioning, Rss k,m That is, the mth signal strength data in the kth received signal strength, m is the number of signal strengths received by the mobile phone for the kth time (the number of signals received by the beacon this time is m, i.e. a total of m signal strength data is received), the value of m will affect whether the subsequent fingerprint positioning can be successfully matched.

[0057] S20: obtaining a direct prediction position of the target traveling vehicle by using a fingerprint matching positioning method according to the signal strength set;

[0058] In the specific implementation process, the direct prediction position refers to the coordinate position obtained by the fingerprint matching positioning method. The fingerprint matching positioning method is a commonly used method in various existing indoor positioning technologies. The basic principle is to abstract and formalize the characteristics of the positioning environment, use the received signal strength indication sequence of each access point (signal source) in the positioning environment to describe the position information in the positioning environment, and realize the collection of these signal strength sequences to establish a position fingerprint database. When a user actually locates, the signal strength sequence measured in real time is matched with the position fingerprint information in the position fingerprint database, and the result with the best matching similarity is selected as the position estimation. This method has good positioning stability, but the positioning response is slow and cannot meet the high refresh rate requirement of vehicle positioning and navigation.

[0059] Specifically, the fingerprint matching is performed according to the signal strengths in the signal strength set to obtain a direct prediction position. In the signal strength set, the maximum value of the signal strengths of the signal sources received in the kth positioning is Rss k,p , and can be specifically represented as: Rss k,p = max(Rss k，1 , Rss k，2 , …, Rss k,m ), (x″′ k , y″′ k ) is the coordinate of the direct prediction position obtained by the fingerprint matching method in the kth positioning, x p , y p is the coordinate of the signal source corresponding to Rss k，p , and (x″′ k , y″′ k ) = (x p , y p ).

[0060] S30: According to the direct prediction position, the operation prediction position of the target vehicle is obtained by using a multi-signal source weighted solution method.

[0061] In the specific implementation process, the response speed of the fingerprint matching positioning method is slow, and it is difficult to meet the high refresh rate requirement of the vehicle positioning and navigation. Therefore, the direct prediction position (x″′ k , y″′ k ) is processed by the multi-signal source weighted solution method to obtain the operation prediction position (x″ k , y″ k ). The multi-signal source weighted solution method is a method for calculating the operation prediction position and the corresponding weight value by using the direct prediction position and different signal strength conditions. The multi-signal source weighted solution method ensures stable positioning output and improves the response speed. The update efficiency of the vehicle positioning can be met when the vehicle speed is high. In addition, the method can eliminate a large number of non-contributing signal sources. When a single signal source cannot provide effective positioning data, other signal sources nearby are introduced to ensure the accuracy of positioning.

[0062] S40: According to the operation prediction position, the positioning position of the target vehicle is obtained.

[0063] In the specific implementation process, the operation prediction position and the last (k-1th) positioning position are obtained by using the weighted method to obtain the current (kth) positioning position, that is, the coordinate position (x′ k , y′ k ) obtained by the positioning algorithm. In actual use, the positioning position can meet the stable high refresh positioning requirement in the scene where the vehicle speed is more than 15Km / h.

[0064] As an optional implementation, the step of obtaining the positioning position of the target moving vehicle according to the operation prediction position comprises: obtaining the positioning position according to the following relationship:

[0065] (x′ k ,y′ k )=(x′ k-1 ,y′ k-1 )+α·(x″ k -x′ k ,y″ k -y′ k )

[0066] wherein, a is the weight value of the kth positioning, (x′ k-1 ,y′ k-1 ) is the coordinate of the positioning position of the (k-1)th positioning, (x″ k ,y″ k ) is the coordinate of the operation prediction position of the kth positioning, and (x′ k ,y′ k ) is the coordinate of the positioning position of the kth positioning.

[0067] In the specific implementation process, after the operation prediction position (x″ k ,y″ k ) is obtained, the positioning position of the target moving vehicle is obtained according to the following relationship:

[0068] (x′ k ,y′ k )=(x′ k-1 ,y′ k-1 )+α·(x″ k -x′ k ,y″ k -y′ k )

[0069] wherein, a is the weight value of the kth positioning, which can be obtained according to the multi-signal source weighted solution method or actual situation, (x′ k-1 ,y′ k-1 ) is the coordinate of the positioning position of the (k-1)th positioning, (x″ k ,y″ k ) is the coordinate of the operation prediction position of the kth positioning, and (x′ k ,y′ k ) is the coordinate of the positioning position of the kth positioning.

[0070] By simplifying the above formula, an increment value can be introduced, and the calculation formula of x′ k and y′ k is obtained.

[0071] x' k = x' k-1 + Δ Rx

[0072] y' k = y' k-1 + Δ Ry

[0073] wherein (x' k , y' k ) is the coordinate of the positioning position of the kth positioning, (x' k-1 , y' k-1 ) is the coordinate of the positioning position of the (k-1)th positioning, Δ Rx is the increment value of the x direction of the present positioning, Δ Ry is the increment value of the y direction of the present positioning, the increment values of the x and y directions can be obtained by operating the predicted position and the weight value, and then the positioning position of the target running vehicle is calculated.

[0074] In the actual vehicle positioning situation, the signal source positions participating in positioning in the parking lot are relatively fixed, and there are many low-energy and non-contributing signal sources in the signals received by the terminal device, which will seriously affect the distinguishability of positioning, so that the program has large calculation amount, slow response, and low accuracy. In the current high-speed vehicle scene, it is difficult to meet the stable, accurate and high refresh positioning. The embodiments of the method set the following conditions: according to different conditions, the signal sources meeting the conditions are selected to participate in the calculation of the predicted position, and the threshold parameters of each screening condition are set through the theoretical attenuation model of RSSI and prior measurement.

[0075] As an optional implementation, the signal strength set comprises signal strengths obtained by multiple positioning; and the step of obtaining the operation predicted position of the target running vehicle according to the direct predicted position and using the multi-signal source weighted solution algorithm comprises:

[0076] judging whether the positioning number is greater than a preset positioning number;

[0077] If yes, the operation predicted position is obtained according to the direct predicted position and the size relationship between the maximum value in the signal strength of each positioning and a preset threshold.

[0078] In the implementation process, the positioning position calculation of a certain positioning needs to use the last positioning position. When the user newly enables or resets the calculation program, there is no historical data available in the program, or the content of the historical data is not sufficient to support subsequent calculation, etc. Therefore, the preset positioning number needs to be set according to the actual use scene of the user. If the positioning number is greater than the preset number, the original predicted position can be obtained by using a multi-signal source weighting algorithm according to the signal strength data in each positioning and the direct predicted position.

[0079] Specifically, the threshold parameter of the screening condition mentioned in the above method needs to be obtained according to the size relationship between the maximum value in the signal strength in each positioning and the preset threshold value, wherein the preset threshold value is Rss i , i = 1, 2, 3, 4, which represents the signal strength of the signal source measured by the terminal device at a position with a distance of i times the standard distance from the signal source.

[0080] There are two determination methods for the four preset threshold values as follows:

[0081] Method one: the conversion formula of the distance r′ i of the terminal device from the i-th beacon and the measured signal strength value Rss i is as follows: Rss i = Rss io - 10 · n · lg r′ i , wherein Rss i is the signal strength of the signal source measured by the terminal device at a position with a distance of i times the standard distance from the signal source, Rss io is the signal strength of the terminal device when the distance from the i-th signal source is 1 meter, r′ i is the distance of the terminal device from the i-th signal source, and n is the radio wave signal strength attenuation factor.

[0082] The radio wave signal strength attenuation factor n is determined by environmental factors, etc. The attenuation factor can be inversely deduced by measuring the signal strength value at different distances several times according to the actual environment, and the calculation formula is as follows:

[0083]

[0084] , wherein n is the radio wave signal strength attenuation factor, rssi do is the signal strength value measured by the terminal device when the distance from the signal source is d0 meters, rssi dx is the signal strength value measured by the terminal device when the distance from the signal source is d x meters, d x is the distance of the terminal device from the signal source during actual measurement, and d0 is the distance used when the signal source is factory calibrated signal strength, which is 1 m by default.

[0085] In actual calculations, multiple measurements are performed (generally 5-10 times), each measuring 5 different distances. The attenuation factor *n* of the radio wave signal strength is calculated by substituting these measurements into the formula above. Then, *n* is substituted into the conversion formula above, and *r′* is calculated accordingly. i The values ​​are set to i times the standard distance d, i.e., d, 2d, 3d, 4d, thus obtaining the values ​​of Rss1, Rss2, Rss3, and Rss4. Normally, the distances between adjacent signal sources are equal; the standard distance is the distance between adjacent signal sources.

[0086] Method 2: Use a terminal device to measure the signal strength at distances d, 2d, 3d, and 4d from the signal source, respectively, for 2 minutes, and take the median of the data, which are Rss1, Rss2, Rss3, and Rss4.

[0087] As an optional implementation, after the step of determining whether the number of positioning attempts is greater than the preset number of positioning attempts, the method further includes:

[0088] If not, then the calculated predicted position is determined as the direct predicted position.

[0089] In practice, if the number of positioning attempts is less than the preset number, the amount of information obtained is relatively small. Therefore, the directly predicted position is used as the calculated predicted position, i.e.:

[0090] x″ k =x″′ k

[0091] y″ k =y″′ k

[0092] Among them, (x″ k ,y″ k (x″′) represents the coordinates of the predicted position from the k-th positioning operation. k ,y″′ k ) represents the coordinates of the directly predicted position of the k-th positioning.

[0093] At this point, the weight value is 1, i.e., Δ Rx =x″ k -x′ k-1 Δ Ry =y″ k -y′ k-1 , where Δ Rx Δ is the incremental value in the x-direction for this positioning. Ry This is the incremental value in the y-direction for this positioning, (x′) k-1 ,y′ k-1 ) represents the coordinates of the location of the (k-1)th positioning.

[0094] As an optional implementation, the preset threshold is Rss1, Rss1 representing the signal strength of the signal source measured by the terminal device at a standard distance position from the signal source;

[0095] If yes, the step of obtaining the operation predicted position according to the direct predicted position and the size relationship between the maximum value in the signal strength in each positioning and the preset threshold comprises:

[0096] If the maximum value in the signal strength is greater than or equal to Rss1, the operation predicted position is determined as the direct predicted position.

[0097] In the specific implementation, if the preset positioning times is l, from the (l+1)th time, if the maximum value in the signal strength is greater than or equal to Rss1, i.e. Rss k，p ≥Rss1, it can be judged that the signal source position corresponding to the signal strength is near the direct predicted position (x″ k ,y″ k ), so the direct predicted position is directly used as the operation predicted position, i.e.

[0098] x″ k =x″′ k

[0099] y″ k =y″′ k

[0100] Wherein, (x″ k ,y″ k ) is the coordinate of the operation predicted position in the kth positioning, (x″′ k ,y″′ k ) is the coordinate of the direct predicted position in the kth positioning.

[0101] At this time, the weight value is 1, i.e. Δ Rx =x″ k -x′ k-1 , Δ Ry =y″ k -y′ k-1 , wherein, Δ Rx is the increment value of the x direction in the current positioning, Δ Ry is the increment value of the y direction in the current positioning, (x′ k-1 , y′ k-1 ) is the coordinate of the positioning position in the (k-1)th positioning.

[0102] As an optional implementation, the preset threshold is Rss1 and Rss2, Rss1 represents the signal strength of the signal source measured by the terminal device at a position with a standard distance from the signal source, and Rss2 represents the signal strength of the signal source measured by the terminal device at a position with a distance of 2 times the standard distance from the signal source.

[0103] If yes, the step of obtaining the operation predicted position according to the direct predicted position and the size relationship between the maximum value in the signal strength and the preset threshold in each positioning comprises:

[0104] If the maximum value in the signal strength is greater than or equal to Rss2 and less than Rss1, the operation predicted position is obtained according to the following relationship:

[0105]

[0106]

[0107] wherein (x″ k ,y″ k ) is the coordinate of the operation predicted position in the kth positioning, (x″′ k ,y″′ k ) is the coordinate of the direct predicted position in the kth positioning, r k,min1 , r k,min2 are the minimum value and the second minimum value in the distance corresponding to the signal strength of each signal source, x″ k,min1 , y″ k,min1 are the coordinate values of the signal source corresponding to r k,min1 , x″ k，min2 , y″ k,min2 are the coordinate values of the signal source corresponding to r k，min2 .

[0108] In the specific implementation process, if the preset positioning number is l, starting from the (l+1)th time, if the maximum value in the signal strength is greater than or equal to Rss2 and less than Rss1, that is, Rss1>Rss k,p ≥Rss2, it can be judged that the signal source position corresponding to the signal strength is at a position with a distance of 1 signal source from the direct predicted position (x″ k ,y″ k ), and the operation predicted position can be calculated according to the following formula:

[0109]

[0110]

[0111] wherein (x″ k ,y″ k) is the coordinate of the operation predicted position of the kth positioning, (x k ,y k ) is the coordinate of the direct predicted position of the kth positioning, r k,min1 ,r k,min2 is the minimum and the second minimum of the distances corresponding to the signal strengths of the respective signal sources, x k,min1 ,y k,min1 is the coordinate value of the signal source corresponding to r k,min1 . k,min2 k,min2 is the coordinate value of the signal source corresponding to r k,min2 .

[0112] r k,min1 ,r k,min2 is determined as follows:

[0113] First, according to the calculation method of the distance corresponding to the signal strength, the distance corresponding to all the signal strengths in r is calculated to obtain the distance vector r wherein, is the set of distances converted from the signal strengths of the signal sources received in the kth time, r k,m is the distance value calculated from the signal strength of the mth signal source received in the kth time; then, r is sorted to find the two smallest values r k，min1 ,r k，min2 ; finally, it is determined whether the following condition is satisfied: λ is a threshold determination factor, if the condition is satisfied, the r k,min1 ,r k,min2 can be used.

[0114] At this time, the weight value is taken as 0.75, i.e. Δ Rx = 0.75·(x k -x k-1 ), Δ Ry = 0.75·(y k -y k-1 ), wherein Δ Rx is the incremental value of the x direction of the present positioning, Δ Ry is the incremental value of the y direction of the present positioning, (x k-1 ,y k-1 ) is the coordinate of the positioning position of the k-1th positioning.

[0115] As an optional implementation, the preset threshold values are Rss2 and Rss3, Rss2 represents the signal strength of the signal source measured by the terminal device at a position 2 times the standard distance from the signal source, and Rss3 represents the signal strength of the signal source measured by the terminal device at a position 3 times the standard distance from the signal source.​

[0116] If so, the step of obtaining the operation predicted position according to the direct predicted position and the maximum value in the signal strength in each positioning and the size relation with the preset threshold comprises:

[0117] If the maximum value in the signal strength is greater than or equal to Rss3 and less than Rss2, the operation predicted position is obtained according to the following relation:

[0118]

[0119]

[0120] Wherein, (x" k ,y" k ) is the coordinate of the operation predicted position in the kth positioning, (x" k ,y" k ) is the coordinate of the direct predicted position in the kth positioning, r k,min1 , r k,min2 is the minimum value and the second minimum value in the distance corresponding to the signal strength of each signal source, x" k,min1 , y" k,min1 is the coordinate value of the signal source corresponding to r k,min1 , x" k,min2 , y" k,min2 is the coordinate value of the signal source corresponding to r k,min2 .

[0121] In the specific implementation process, if the preset positioning times is l, from the l+1th, if the maximum value in the signal strength is greater than or equal to Rss3 and less than Rss2, that is, Rss2>Rss k,p ≥Rss3, it can be judged that the signal source position corresponding to the signal strength is at the position of 2 signal sources away from the direct predicted position (x" k ,y" k ), and the operation predicted position can be calculated according to the following formula:

[0122]

[0123]

[0124] Wherein, (x" k ,y" k ) is the coordinate of the operation predicted position in the kth positioning, (x" k ,y" k ) is the coordinate of the direct predicted position in the kth positioning, r k,min1 , r k,min2x″ represents the minimum and second minimum distances corresponding to the signal strengths of each of the aforementioned signal sources. k,min1 y″ k,min1 For r k,min1 The coordinates of the corresponding signal source, x″ k,min2 y″ k,min2 For r k,min2 The coordinates of the corresponding signal source.

[0125] r k,min1 r k,min2 The method for determining this is as follows:

[0126] First, based on the above method for calculating the distance corresponding to signal strength, calculate... The distance vector is obtained by matching the distances corresponding to all signal strengths. in, Let r be the set of signal strengths received from the k-th signal source, converted into distances. k,m The distance value is calculated from the signal strength of the m-th signal source received in the k-th iteration; then, for Sort the data and find the two values ​​r with the smallest distance. k,min1 ,r k,min2 Finally, determine whether the condition is met. λ is the threshold decision factor; if it satisfies the condition, then r... k,min1 ,r k,min2 Available.

[0127] At this point, the weight value is taken as 0.5, i.e., Δ. Rx =0.5·(x″) k -x′ k-1 ), Δ Ry =0.5·(y″) k -y′ k-1 ), where Δ Rx Δ is the incremental value in the x-direction for this positioning. Ry This is the incremental value in the y-direction for this positioning, (x′) k-1 ,y′ k-1 ) represents the coordinates of the location of the (k-1)th positioning.

[0128] As an optional implementation, the preset thresholds are Rss3 and Rss4, where Rss3 represents the signal strength of the signal source measured by the terminal device at a position three times the standard distance from the signal source, and Rss4 represents the signal strength of the signal source measured by the terminal device at a position four times the standard distance from the signal source.

[0129] If so, the step of obtaining the calculated predicted position based on the directly predicted position and the relationship between the maximum value of the signal strength in each positioning and a preset threshold includes:

[0130] If the maximum value in the signal strength is greater than or equal to Rss4 and less than Rss3, the operation predicted position is determined as the direct predicted position, and a weight value is obtained according to the following relationship:

[0131]

[0132] wherein a is the weight value of the kth positioning, used for calculating the positioning position, (x" k ,y" k ) is the coordinate of the operation predicted position of the kth positioning, (x' k-1 ,y' k-1 ) is the coordinate of the positioning position of the (k-1)th positioning, and d is the distance value of the adjacent signal source.

[0133] In the specific implementation process, if the preset positioning number is l, starting from the (l+1)th, if the maximum value in the signal strength is greater than or equal to Rss4 and less than Rss3, i.e. Rss3>Rss k,p ≥Rss4, it can be judged that the signal source position corresponding to the signal strength is at a position greater than the interval of 2 signal sources from the direct predicted position (x" k ,y" k ), and the direct predicted position is directly used as the operation predicted position, i.e.

[0134] x" k =x" k

[0135] y" k =y" k

[0136] wherein (x" k ,y" k ) is the coordinate of the operation predicted position of the kth positioning, and (x" k ,y" k ) is the coordinate of the direct predicted position of the kth positioning.

[0137] At this time, the weight value should be:

[0138]

[0139] wherein a is the weight value of the kth positioning, used for calculating the positioning position, (x" k ,y" k ) is the coordinate of the operation predicted position of the kth positioning, (x' k-1 ,y' k-1 ) is the coordinate of the positioning position of the (k-1)th positioning, and d is the standard distance.

[0140] The incremental values in x and y directions are obtained as follows:

[0141]

[0142]

[0143] wherein Δx(k) is the incremental value in the x direction of the present positioning, Δy(k) is the incremental value in the y direction of the present positioning, and (x'(k), y'(k)) is the coordinate of the positioning position of the k-1th positioning. Rx Ry k-1 k-1

[0144] As an optional embodiment, the preset threshold value is Rss4, Rss4 representing the signal strength of the signal source measured by the terminal device at a position 4 times the standard distance from the signal source; if the maximum value in the signal strength is less than Rss4, the signal source corresponding to the signal strength does not participate in the present positioning.

[0145] In the specific implementation process, when the preset positioning number is l, starting from the (l+1)th, if the maximum value in the signal strength is less than Rss4, i.e., Rss4>Rss k,p , it can be judged that the signal strength value of the signal source corresponding to the signal strength is too low, and the signal source does not participate in the present positioning.

[0146] It should be understood that the above is only for illustration, and does not constitute any limitation on the technical solutions of the present application. Those skilled in the art can make settings based on needs in actual application, which is not limited herein.

[0147] As can be seen from the above description, the present embodiment is to obtain a direct prediction position by a fingerprint matching method according to the wireless signals emitted by the signal sources in the surrounding environment and measured by the terminal device, and then obtain an operation prediction position by a multi-signal source weighted solution method from the direct prediction position. The current positioning position is obtained by weighting the operation prediction position and the last positioning position. The stability of the fingerprint matching method is ensured, and the positioning response speed is improved by the multi-signal source weighted solution method, ensuring the accuracy of the positioning. The requirement of high refresh rate of the vehicle positioning and navigation at high vehicle speed is met, and the overall efficiency of the positioning is improved. Further, the signal sources meeting the conditions are selected according to different situations to participate in the calculation of the operation prediction position, so that the effective signal sources are dynamically and real-timely selected, and the calculation of the operation prediction position and the final positioning position is more accurate.

[0148] ​​​​Furthermore, in an embodiment, the embodiments of the present application also provide a computer device, which can be a mobile phone, a tablet, a desktop computer, etc., comprising a processor, a memory, and a computer program stored in the memory, which, when executed by the processor, implements the steps of the method in the foregoing embodiments.

[0149] Furthermore, in an embodiment, the embodiments of the present application also provide a computer storage medium, which stores a computer program, which, when executed by a processor, implements the steps of the method in the foregoing embodiments.

[0150] It should be noted that, in this document, the terms "comprising" and "including" or any other variant thereof are intended to cover non-exclusive inclusions, such that processes, methods, articles, or systems that comprise a list of elements do not include only those elements in the list, but also other elements that are not expressly listed, or other elements inherent in such processes, methods, articles, or systems. Without further limitation, an element defined by the phrase "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or system that includes the element.

[0151] The above-mentioned serial numbers of the embodiments of the present application are only for description, and do not represent the advantages or disadvantages of the embodiments.

[0152] From the above description of the embodiments, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be realized by means of software and a necessary general hardware platform, and of course, they can also be realized by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical solutions of the present application can be embodied in the form of a software product, which is stored in a storage medium (such as a read-only memory / random access memory, a magnetic disk, an optical disk), and includes a plurality of instructions for causing a multimedia terminal device (which can be a mobile phone, a computer, a television receiver, or a network device, etc.) to execute the methods described in the embodiments of the present application.

[0153] The above is only the preferred embodiment of the present application, and does not limit the patent scope of the present application, and any equivalent structure or equivalent process transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A parking lot vehicle positioning method based on a signal source, characterized in that, For a terminal device, the terminal device being located inside the target moving vehicle, the following steps are included: It receives wireless signals emitted by multiple signal sources located in the parking lot and obtains a set of signal strengths; Based on the signal strength set, the direct predicted position of the target moving vehicle is obtained using the fingerprint matching positioning method. Based on the directly predicted position, the calculated predicted position of the target moving vehicle is obtained using a multi-signal source weighted solution algorithm, specifically including: determining whether the number of positioning attempts is greater than the preset number of positioning attempts; If so, then based on the directly predicted location and the relationship between the maximum signal strength in each positioning and a preset threshold, the preset threshold is: , The signal strength of the signal source is measured by the terminal device at a standard distance from the signal source, and the calculated predicted position is obtained. The method for obtaining the predicted position specifically includes: if the maximum value in the signal strength is greater than or equal to... If so, the calculated predicted position is determined as the direct predicted position.

2. The parking lot vehicle positioning method based on signal source as described in claim 1, characterized in that, After the step of determining whether the number of positioning attempts is greater than the preset number of positioning attempts, the method further includes: if not, determining the calculated predicted position as the direct predicted position.

3. The parking lot vehicle positioning method based on a signal source according to claim 1, characterized in that, The step of obtaining the location of the target vehicle based on the calculated predicted location includes: The positioning location is obtained according to the following relationship: ； Where a is the weight value of the k-th positioning, (x′ k-1 y′ k-1 (x″) represents the coordinates of the (k-1)th positioning position. k , y″ k (x′) represents the coordinates of the predicted position from the k-th positioning operation. k y′ k ) represents the coordinates of the location at the k-th positioning.

4. The parking lot vehicle positioning method based on signal source according to claim 1, characterized in that, The preset threshold is replaced with and , This indicates the signal strength of the signal source as measured by the terminal device at a standard distance from the signal source. This indicates the signal strength of the signal source as measured by the terminal device at a distance of twice the standard distance from the signal source; The method for obtaining the predicted position is replaced by: If the maximum value of the signal strength is greater than or equal to and less than The predicted position is then obtained according to the following relationship: ； ； in, The coordinates of the predicted position are for the k-th positioning operation. Let be the coordinates of the directly predicted position for the k-th positioning. , These are the minimum and second minimum distances corresponding to the signal strengths of each of the aforementioned signal sources. , for The coordinates of the corresponding signal source, , for The coordinates of the corresponding signal source.

5. The parking lot vehicle positioning method based on a signal source according to claim 1, characterized in that, The preset threshold is replaced with and , This indicates the signal strength of the signal source as measured by the terminal device at a distance of twice the standard distance from the signal source. This indicates the signal strength of the signal source as measured by the terminal device at a distance of 3 times the standard distance from the signal source; The method for obtaining the predicted position is replaced by: If the maximum value of the signal strength is greater than or equal to and less than The predicted position is then obtained according to the following relationship: ； ； in, The coordinates of the predicted position are for the k-th positioning operation. Let be the coordinates of the directly predicted position for the k-th positioning. , These are the minimum and second minimum distances corresponding to the signal strengths of each of the aforementioned signal sources. , for The coordinates of the corresponding signal source, , for The coordinates of the corresponding signal source.

6. The parking lot vehicle positioning method based on a signal source according to claim 1, characterized in that, The preset threshold is replaced with and , This indicates the signal strength of the signal source as measured by the terminal device at a distance of 3 times the standard distance from the signal source. This indicates the signal strength of the signal source as measured by the terminal device at a distance of 4 times the standard distance from the signal source; The method for obtaining the predicted position is replaced by: If the maximum value of the signal strength is greater than or equal to and less than Then, the calculated predicted position is determined as the direct predicted position, and the weight value is obtained according to the following relationship: ； in, The weight value for the k-th positioning is used to calculate the positioning location. The coordinates of the predicted position are for the k-th positioning operation. Let d be the coordinates of the (k-1)th positioning location, and d be the standard distance.

7. A computer device, characterized in that, The computer device includes a memory and a processor, wherein the memory stores a computer program and the processor executes the computer program to implement the method as described in any one of claims 1-6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program, and the processor executes the computer program to implement the method as described in any one of claims 1-6.

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