CN108508404A - A kind of localization method and system based on aerial array - Google Patents

Abstract

Embodiments of the present invention provide a positioning method and system based on an antenna array. The method includes: based on the TOA algorithm and the TDOA algorithm, obtaining the distance between the target object and each antenna in the antenna array to form a distance set; based on the distance set, positioning the target object. An antenna array-based positioning method and system provided by the embodiments of the present invention uses TOA algorithm and TDOA fusion as a fusion algorithm to measure the distance of the target object first, and then locates the target object according to the distance measurement result. The accuracy of the distance set obtained by using this fusion algorithm is high, and the iterative algorithm is not used to locate the target object according to the ranging result, and it has a strong anti-obstruction effect, so the final positioning result must be Near the real position of the target object, it is very stable. Therefore, the method improves the localization rate, localization accuracy and localization robustness.

Description

A positioning method and system based on antenna array

technical field

Embodiments of the present invention relate to the technical field of antenna positioning, and in particular, to a positioning method and system based on an antenna array.

Background technique

The global satellite navigation system (GNSS) has the advantages of wide coverage, high accuracy and good reliability in outdoor environments. But indoors, the satellite signal becomes weak, making the positioning accuracy poor; even outdoors, the general positioning accuracy is above the meter level. However, due to the low distribution density of mobile communication base stations (BS), even if multiple base stations are used to measure the distance through the trilateral time of arrival, the positioning accuracy is more than tens of meters.

At present, positioning technologies that have been used for indoor positioning include ultra-wideband, Bluetooth, infrared, WiFi, ZigBee, and radio frequency identification. Among them, an ultra-wideband technology (Ultra-wide bandwidth, UWB) can provide a robust transmission signal, and the transmission signal has a strong ability to pass through walls and a high resolution. Moreover, positioning using ultra-wideband technology has the characteristics of low power consumption, low system complexity, strong anti-multipath interference capability and high ranging accuracy. Therefore, ultra-wideband technology is expected to be applied to high-precision positioning in indoor complex environments, and it will show more superior performance.

However, in practical applications, there are still some difficulties that have not been resolved by using ultra-wideband technology for positioning. For example, when using ultra-wideband technology for positioning, the TDOA algorithm is usually used for positioning, but when using the TDOA algorithm for positioning, it is necessary to use an iterative algorithm to solve the coordinates of the target object. The solution rate of this method is relatively low, so the positioning rate is low. ; and when the antenna topology is small, it will cause a large error in the positioning result, and even fail to converge, which can be proved by deriving the Cramerau lower bound of the positioning error under this topology.

Contents of the invention

Embodiments of the present invention provide a positioning method and system based on an antenna array, which are used to solve the defects of low positioning rate and low positioning accuracy in the prior art, and improve the positioning rate and positioning accuracy.

An embodiment of the present invention provides a positioning method based on an antenna array, including:

Based on the TOA algorithm and the TDOA algorithm, the distance between the target object and each antenna in the antenna array is obtained to form a distance set;

Based on the set of distances, the target object is located.

An embodiment of the present invention provides a positioning system based on an antenna array, including:

The distance set acquisition module is used to obtain the distance between the target object and each antenna in the antenna array based on the TOA algorithm and the TDOA algorithm to form a distance set;

A positioning module, configured to locate the target object based on the set of distances.

The antenna array-based positioning method and system provided by the embodiments of the present invention use TOA algorithm and TDOA fusion as a fusion algorithm to measure the distance of the target object first, and then locate the target object according to the distance measurement result. The accuracy of the distance set obtained by using this fusion algorithm is high, and the iterative algorithm is not used to locate the target object according to the ranging result, and it has a strong anti-obstruction effect, so the final positioning result must be Near the real position of the target object, it is very stable. Therefore, the method improves the localization rate, localization accuracy and localization robustness.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

FIG. 1 is a flowchart of an embodiment of a positioning method based on an antenna array in the present invention;

FIG. 2 is a schematic diagram of a ranging process in an embodiment of a positioning method based on an antenna array according to the present invention;

3 is a schematic diagram of a positioning process in an embodiment of a positioning method based on an antenna array according to the present invention;

Fig. 4 is a structural block diagram of an embodiment of a positioning device based on an antenna array according to the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments It is a part of embodiments of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Fig. 1 is a flowchart of an embodiment of a positioning method based on an antenna array according to the present invention. As shown in Fig. 1, the method includes:

Based on the TOA algorithm and the TDOA algorithm, the distance between the target object and each antenna in the antenna array is obtained to form a distance set; based on the distance set, the target object is positioned.

Different from the methods in the prior art that only use the TOA algorithm or the TDOA algorithm for positioning, the method provided by the embodiment of the present invention uses the TOA algorithm and the TDOA algorithm as a fusion algorithm to first measure the distance of the target object, and then use the distance measurement result Locate the target object.

The purpose of the method provided by the embodiment of the present invention is to locate the target object. Specifically, the hardware device for implementing the method is at least the following two items: an antenna array and a mobile tag. Wherein, the antenna array can be located at any position, and the antenna array includes at least three antennas; the mobile tag is set on the target object, and the mobile tag is also provided with antennas. The target object may be a walking crowd, an unmanned car or a drone, etc., which is not limited in this embodiment of the present invention.

Based on the TOA algorithm and TDOA algorithm, the distance is measured according to the ultra-wideband signal sent between the mobile tag and the antenna array, and then the target object is positioned through the distance measurement result. It should be noted that the anti-occlusion positioning algorithm is used in the process of locating the target object through the ranging result. Wherein, the anti-occlusion positioning algorithm is an anti-non-line-of-sight position solving algorithm, preferably a positioning algorithm based on least squares in the embodiment of the present invention.

In the method provided by the embodiment of the present invention, the distance measurement of the target object is carried out by fusing the TOA algorithm and the TDOA algorithm as the fusion algorithm, and then the target object is positioned by the anti-occlusion positioning algorithm and the distance measurement result. The accuracy of the distance set obtained by using the fusion algorithm is high, and the anti-occlusion positioning algorithm is not an iterative algorithm, and has a strong anti-obstacle occlusion effect, so the final positioning result must be at the real position of the target object Nearby, very stable. Therefore, the method improves the localization rate, localization accuracy and localization robustness.

Based on the foregoing embodiments, the embodiments of the present invention specifically describe the ranging process. Based on the TOA algorithm and the TDOA algorithm, the distance between the target object and each antenna in the antenna array is obtained to form a distance set, which further includes:

Based on the TOA algorithm, obtain the first distance between the target object and any antenna in the antenna array; based on the TDOA algorithm, obtain the distance between each antenna in the other antennas in the antenna array and the any antenna. second distance; according to the first distance and all the second distances, obtain a third distance between the target object and each antenna in the other antennas; and combine the first distance and all the second distances The third distance constitutes the distance set; wherein, the other antennas are all remaining antennas in the antenna array after removing the any antenna.

The following describes the ranging process in the embodiment of the present invention through specific examples:

The number of antennas in the antenna array is preferably 4, which are antenna No. 1, antenna No. 2, antenna No. 3, and antenna No. 4. "Any antenna" is preferably antenna No. 1, and "other antennas" are antenna No. 2, antenna No. 3, and antenna No. 4. It should be noted that the clocks of all antennas in the antenna array are synchronized.

Figure 2 is a schematic diagram of the ranging process in an embodiment of a positioning method based on an antenna array according to the present invention. As shown in Figure 2, the mobile tag sends a request frame to the antenna array, and records antenna No. 1, antenna No. 2, antenna No. 3 and The time t ₁ , t ₂ , t ₃ , and t ₄ of the request frame are received by antenna No. 4 respectively, and three sets of TDOA differential values t ₂₁ =t ₂ -t ₁ , t ₃₁ =t ₃ -t ₁ , t ₄₁ are calculated =t ₄ -t ₁ . It should be noted that the clocks of the four antennas are synchronized, so the three sets of TDOA differential values obtained are of high precision. Multiply the three sets of TDOA differential values by the speed of light to obtain the request frame arriving at the No. 2 antenna and its arriving at the No. 1 antenna. The distance difference d ₂₁ =c×t ₂₁ , the distance difference between the request frame reaching the No. 3 antenna and the No. 1 antenna d ₃₁ =c×t ₃₁ , the distance difference between the request frame reaching the No. 4 antenna and the No. 1 antenna d ₄₁ =c×t ₄₁ .

Antenna 1 sends a response frame to the mobile tag, and the mobile tag records the arrival time of the response frame, and sends a response frame to the antenna array, and records the response received by antenna 1, antenna 2, antenna 3 and antenna 4 respectively Frame time t _1n , t _2n , t _3n , t _4n , and calculate three sets of TDOA differential values t _21n =t _2n -t _1n , t _31n =t _3n -t _1n , t _41n =t _4n -t _1n . Multiply the three sets of TDOA differential values by the speed of light to obtain the distance difference d _21n =c×t _21n between the response frame reaching the No. 2 antenna and the No. 1 antenna, and the distance between the response frame reaching the No. 3 antenna and the No. 1 antenna The difference d _31n =c×t _31n , the distance difference d _41n =c×t _41n between the response frame arriving at the No. 4 antenna and its reaching the No. 1 antenna.

Use the TOA algorithm to calculate the distance d ₁ between the mobile tag and antenna No. 1, and then calculate the average value of the distance difference between the mobile tag and antenna No. , and the distances of antenna No. 4 are: d ₂ =d ₁ +(d ₂₁ +d _21n )/2, d ₃ =d ₁ +(d ₃₁ +d _31n )/2, d ₄ =d ₁ +(d ₄₁ +d _41n )/2. It should be noted that the set composed of d ₁ , d ₂ , d ₃ and d ₄ is the distance set mentioned in the embodiment of the present invention.

In the method provided by the embodiment of the present invention, by synchronizing the clocks of all antennas in the antenna array and introducing TDOA measurement in the ranging process of the TOA algorithm, the mobile tag and the antenna array can obtain the mobile tag in a complete TOA ranging process The distance to each antenna in the antenna array greatly improves the ranging efficiency. At the same time, clock synchronization can eliminate synchronization errors between different antennas, greatly improving the accuracy of ranging results, and further greatly improving the accuracy of subsequent positioning results based on ranging results. Moreover, since the influence of non-line-of-sight on TDOA measurement can be reduced when the antenna array has a small topology, it has better stability. Using this method, high precision can be maintained even when the antenna array has a very small topology. positioning effect.

Based on the foregoing embodiments, the embodiment of the present invention describes the process of locating a target object based on a ranging result. Positioning the target object based on the distance set further includes:

On the plane where the antenna array is located, a Cartesian coordinate system is established with the center of the antenna array as the origin of coordinates; with the origin of the coordinates as the center, a circle is made with the median of the distance set as the radius; in the Perform multi-point sampling on the circle, and for each sampling point, obtain the distance between the sampling point and each antenna in the antenna array and form a candidate distance set; based on the least square method, according to all the candidate distance sets and the The distance set is used to locate the target object.

Wherein, based on the least squares method, according to all the candidate distance sets and the distance sets, the target object is positioned, further comprising:

For each of the candidate distance sets, obtain the mean square error of each distance in the candidate distance set and the corresponding distance in the distance set; add all the mean square errors to obtain the corresponding distance of the candidate distance set The mean square error sum; obtain the minimum mean square error sum in the mean square error sum corresponding to all the candidate distance sets, and use the minimum mean square error and the coordinates of the corresponding sampling points as the coordinates of the target object, to realize the positioning of the target object.

The positioning process in the embodiment of the present invention is specifically described below through specific examples:

The antenna array is preferably an antenna array including 4 antennas, namely antenna No. 1, antenna No. 2, antenna No. 3 and antenna No. 4 mentioned in the above embodiments. In the embodiment of the present invention, the four antennas are respectively arranged at four vertices of a rectangle of any size.

Fig. 3 is a schematic diagram of the positioning process in an embodiment of a positioning method based on an antenna array according to the present invention. As shown in Fig. 3, on the plane where the antenna array is located, the center of the antenna array (that is, the center of the rectangle) is used as the coordinate origin, Establish a Cartesian coordinate system. In this coordinate system, antenna No. 1, antenna No. 2, antenna No. 3 and antenna No. 4 are located at points A, B, C and D, respectively. Take the perpendicular line between points B and C as the x-axis, and the perpendicular line between points A and B as the y-axis.

Draw a circle with the origin of the coordinates as the center and the median R of the distance set as the radius, and the coordinates of the mobile label are approximately located on the circle. Multi-point sampling is performed on the circle to obtain multiple sampling points (xi _, y _i ), i=1, 2, . . . , n, where n is the number of sampling points. For each sampling point, calculate the distance d' ₁ , d' ₂ , d' ₃ , d' ₄ from the sampling point to each antenna, and use the above distance as a set of candidate distances, and then calculate the mean square of the above distance and the distance set The sum of errors, for multiple sampling points, there are multiple candidate distance sets, correspondingly, there are multiple sums of mean square errors. The coordinates of the sampling points corresponding to the sum of the minimum mean square errors are used as the position coordinates of the mobile tag (that is, the target object), so as to realize the positioning of the target object. The formula is as follows:

It should be noted that multi-point sampling on the circle can be understood as: multi-point sampling on the entire circle or multi-point sampling in part of the arc segment, multi-point sampling can be equal interval sampling, or non-equal interval sampling.

Based on the foregoing embodiments, as a preferred embodiment, this embodiment of the present invention describes how to determine the sampling range. That is, before multisampling on the circle also include:

Based on the last positioning result of the target object, the current sampling range is determined on the circle.

It can be understood that when the target object is positioned for the first time, it is necessary to perform multi-point sampling on the entire circle to complete the positioning. However, when the target object performs subsequent positioning such as the second, third, and fourth times, the sampling range of this time can be determined according to the previous positioning result to complete the positioning.

Specifically, the last positioning result is recorded, and the current positioning result is only searched in a window near the last positioning result (that is, the coordinates of the target object or the mobile tag). Among them, assuming that the fastest moving speed of the mobile tag is v, multiplied by the time interval τ between two positionings, it is the maximum moving distance of the mobile tag within the time interval between two positionings. The maximum movement distance is converted into the maximum movement angle, which is the window width. Generally, the window can take a fixed value of 40 degrees, that is, sampling is performed within the range of 20 degrees to the left and right of the last positioning result. Therefore, for the second and subsequent positioning results, the positioning results outside the window will be filtered out, because the complex environment or the occlusion of obstacles will affect the ranging accuracy, so filtering the positioning results through the window can improve the stability of the positioning algorithm sex.

Based on the above embodiments, as a preferred embodiment, the embodiment of the present invention considers another situation, that is, how to locate the target object when the antenna array rotates. Multipoint sampling on said circle, previously also included:

Determine whether the antenna array rotates, and if it is determined that the antenna array rotates, determine the current sampling range on the circle according to the rotation angle of the antenna array and the last positioning result of the target object .

Specifically, in practical applications, the antenna array can move freely and complete the relative positioning of the mobile tag. When the antenna array rotates by an angle θ relative to the previous positioning time, moving the tag is equivalent to rotating -θ relative to the antenna array, and the search window at the current moment also rotates -θ. In this way, the rotation angle information of the antenna array can be fully utilized, and the speed of positioning the mobile tag (that is, the target object) can be improved.

The method provided by the embodiment of the present invention records the angle value of the mobile tag relative to the antenna array during the first positioning, and searches around this angle for the next positioning. It should be noted that the ranging result used in the next positioning may change, that is, the radius of the circle will change. The purpose of designing this "window"-based search algorithm is that there may be a large error in the distance between the mobile tag and the antenna array. This error will not cause a drastic change in the radius of the circle, but it may lead to a search on the circle. The results are offset, so the window can improve the search rate, and can also limit the range of the positioning results. When using the least squares method to solve the problem, the variance of the ranging value is used for weighting, which can make the positioning more accurate. Combining the angle change information of the antenna array can also enable the antenna array to quickly locate the target object when it is moving.

Based on the foregoing embodiments, as a preferred embodiment, the embodiment of the present invention takes into account the impact of non-line-of-sight transmission, and corrects the ranging result. The correction process is between ranging and positioning, that is, positioning the target object, and also includes before:

Obtaining the ratio of the power corresponding to the first path to the total power of the waveform according to the waveform of the channel impulse response;

The ratio is compared with a threshold value, and if the ratio is greater than the threshold value, the distance set is corrected.

Specifically, according to the waveform of the channel impulse response (CIR), calculate the ratio of the power corresponding to the first arrival path to the total power of the waveform, the formula is as follows: Q=10×log ₁₀ (F ² /C), where F is the first arrival of the signal The amplitude corresponding to the diameter, C is the total power of the received signal. Compare Q with the preset threshold value to determine whether the ranging result is affected by non-line-of-sight obstructions. When the ratio is greater than the preset threshold value, it is considered that the signal has passed through the obstacle. Therefore, the ranging result should be Subtract a ranging bias. That is, the ranging bias is subtracted from each distance value in the distance set. It should be noted that both the threshold value and the ranging deviation are empirical values.

The method provided by the embodiment of the present invention judges whether the signal has passed through an obstruction, and if so, corrects the ranging result according to experimental experience, which can reduce the impact of non-line-of-sight transmission on distance measurement, improve ranging accuracy, and then Improve positioning accuracy. Therefore, this method is very effective in complex occlusion environments, and can eliminate various non-line-of-sight occlusions on average, ensuring more robust positioning results.

It should be noted that what is acquired in the positioning process in the above embodiment is a two-dimensional coordinate. Therefore, the positioning of the target object also includes:

Obtain the position coordinates of the antenna array and the height difference between the target object and the antenna array.

Specifically, the height information of the target object is acquired according to the position coordinates of the antenna array and the height difference between the target object and the antenna array. The two-dimensional coordinates and the height information of the target object are combined into three-dimensional coordinates, and the three-dimensional coordinates are the spatial position of the target object.

Based on the foregoing embodiments, the target object is positioned, and then further includes:

Clock synchronization is performed on each antenna in the antenna array for next positioning.

Specifically, after each positioning, a clock synchronization operation needs to be performed on the antenna array. It should be noted that the antenna array and mobile tags do not require clock synchronization.

As a preferred embodiment, the embodiment of the present invention describes the hardware structure of the antenna array and the mobile tag.

The antenna array is integrated on one circuit board, which contains ultra-wideband module, clock crystal oscillator, signal antenna (including at least 3 antennas), inertial navigation module and auxiliary circuit. The mobile tag is based on a micro-single-chip microcomputer, including an ultra-wideband module, a chip antenna and an auxiliary circuit.

Both the antenna array and the UWB module in the mobile tag are used to send UWB signals, that is, the various frame signals mentioned in the above embodiments. Both the signal antenna and the patch antenna are used to send and receive UWB signals. A clock crystal is used to synchronize the clocks of all antennas in the antenna array. The inertial navigation module is used to obtain the rotational acceleration of the antenna array to calculate the rotational angle. Both the antenna array and the auxiliary circuits in the mobile tag are used to provide some auxiliary functions, such as power supply.

The mobile tag is located on the target object to be positioned. The target object can be a walking crowd, an unmanned vehicle or a drone. The mobile tag is attached to the chest pocket or shoulder badge of the unmanned vehicle, drone or human body.

The antenna array can be placed in a fixed position to realize the positioning and tracking of unmanned vehicles, drones and human bodies; the antenna array can be placed on unmanned vehicles and drones to realize other unmanned vehicles, drones, and mobile human bodies positioning.

The position of the antenna in the antenna array can be adjusted arbitrarily, as long as the position coordinates of the antenna are known, the relative position of the mobile tag can be determined.

An embodiment of the present invention provides a positioning system based on an antenna array, including:

The distance set acquisition module is used to obtain the distance between the target object and each antenna in the antenna array based on the TOA algorithm and the TDOA algorithm to form a distance set;

A positioning module, configured to locate the target object based on the set of distances.

It should be noted that the system of the embodiment of the present invention can be used to implement the technical solution of the embodiment of an antenna array-based positioning method shown in FIG. 1 , and its implementation principle and technical effect are similar, and will not be repeated here.

Fig. 4 is a structural block diagram of an embodiment of a positioning device based on an antenna array according to the present invention. As shown in Fig. 4, the positioning device includes: a processor (processor) 401, a memory (memory) 402, and a bus 403; wherein, the The processor 401 and the memory 402 communicate with each other through the bus 403; the processor 401 is used to call the program instructions in the memory 402 to execute the methods provided by the above method embodiments, for example including : Based on the TOA algorithm and the TDOA algorithm, the distance between the target object and each antenna in the antenna array is obtained to form a distance set; based on the distance set, the target object is positioned.

An embodiment of the present invention discloses a computer program product, the computer program product includes a computer program stored on a non-transitory computer-readable storage medium, the computer program includes program instructions, and when the program instructions are executed by a computer, The computer can execute the methods provided by the above method embodiments, for example, including: based on the TOA algorithm and the TDOA algorithm, obtaining the distance between the target object and each antenna in the antenna array to form a distance set; based on the distance set, the The target object is positioned.

An embodiment of the present invention provides a non-transitory computer-readable storage medium, the non-transitory computer-readable storage medium stores computer instructions, and the computer instructions cause the computer to execute the methods provided in the above method embodiments, for example The method includes: acquiring the distance between the target object and each antenna in the antenna array based on the TOA algorithm and the TDOA algorithm, and forming a distance set; and positioning the target object based on the distance set.

Those of ordinary skill in the art can understand that all or part of the steps for realizing the above-mentioned method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the It includes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk and other various media that can store program codes.

Through the above description of the implementations, those skilled in the art can clearly understand that each implementation can be implemented by means of software plus a necessary general hardware platform, and of course also by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the prior art can be embodied in the form of software products, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic discs, optical discs, etc., including several instructions to make a computer device (which may be a personal computer, server, or network device, etc.) execute the methods described in various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (10)

1. A positioning method based on antenna array, characterized in that, comprising: Based on the TOA algorithm and the TDOA algorithm, the distance between the target object and each antenna in the antenna array is obtained to form a distance set; Based on the set of distances, the target object is positioned. 2. method according to claim 1, is characterized in that, described based on TOA algorithm and TDOA algorithm, obtains the distance between each antenna in target object and antenna array, forms distance set, further comprises: Obtaining a first distance between the target object and any antenna in the antenna array based on the TOA algorithm; Based on the TDOA algorithm, obtaining a second distance between each antenna in the other antennas in the antenna array and the any antenna; Obtaining a third distance between the target object and each of the other antennas according to the first distance and all the second distances; and combining the first distance and all the third distances the set of distances; Wherein, the other antennas are all remaining antennas in the antenna array after excluding any antenna. 3. The method according to claim 1, wherein the positioning of the target object based on the set of distances further comprises: On the plane where the antenna array is located, a rectangular coordinate system is established with the center of the antenna array as the coordinate origin; Construct a circle with the origin of the coordinates as the center and the median of the distance set as the radius; Perform multi-point sampling on the circle, and for each sampling point, obtain the distance between the sampling point and each antenna in the antenna array and form a candidate distance set; Based on the least squares method, the target object is positioned according to all the candidate distance sets and the distance sets. 4. The method according to claim 3, wherein the least square method is used to locate the target object according to all the candidate distance sets and the distance sets, further comprising: For each set of candidate distances, obtaining a mean square error between each distance in the set of candidate distances and the corresponding distance in the set of distances; Adding all the mean square errors to obtain the sum of mean square errors corresponding to the candidate distance set; Obtain the minimum mean square error sum among the mean square error sums corresponding to all the candidate distance sets, and use the minimum mean square error and the coordinates of the corresponding sampling points as the coordinates of the target object to achieve the target The positioning of the object. 5. The method according to claim 3, wherein said performing multi-point sampling on said circle also includes before: Based on the last positioning result of the target object, the current sampling range is determined on the circle. 6. The method according to claim 3, wherein said performing multi-point sampling on said circle also includes before: Determine whether the antenna array rotates, if it is determined that the antenna array rotates, determine the current sampling range on the circle according to the rotation angle of the antenna array and the last positioning result of the target object . 7. The method according to claim 1, wherein the positioning of the target object also includes before: Obtaining the ratio of the power corresponding to the first path to the total power of the waveform according to the waveform of the channel impulse response; The ratio is compared with a threshold value, and if the ratio is greater than the threshold value, the distance set is corrected. 8. The method according to claim 1, wherein the positioning of the target object further comprises: Obtain the position coordinates of the antenna array and the height difference between the target object and the antenna array. 9. The method according to claim 1, wherein the positioning of the target object further comprises: Clock synchronization is performed on each antenna in the antenna array for next positioning. 10. A positioning system based on an antenna array, characterized in that it comprises: The distance set acquisition module is used to obtain the distance between the target object and each antenna in the antenna array based on the TOA algorithm and the TDOA algorithm to form a distance set; A positioning module, configured to locate the target object based on the set of distances.