Dual-millimeter-wave-radar fusion target detection method, terminal device, and storage medium

Abstract

The application discloses a kind of double millimeter wave radar fusion target detection method, terminal equipment and storage medium, the method includes as follows: obtaining first point cloud data frame and second point cloud data frame under the same time frame;All first point cloud is projected to the spherical coordinate system of second millimeter wave radar from the spherical coordinate system of first millimeter wave radar, obtain the first point cloud set consisting of several first point clouds;The point cloud information of all second point clouds is added to second point cloud set;First point cloud set and second point cloud set are associated and matched, obtain all associated matching point cloud pairs and its point cloud information;The optimal position and absolute motion speed of each associated matching point cloud pair corresponding target in carrier coordinate system are obtained.The application is applied to target detection field, not only can improve the precision of target point detection, but also can output the absolute motion speed size and direction, solve single millimeter wave radar only radial velocity measurement cannot solve the problem of transverse target detection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of target detection, and particularly relates to a dual-millimeter-wave-radar fusion target detection method, a terminal device and a storage medium. BACKGROUND

[0002] As a key sensor component in the field of automobile active safety, the millimeter-wave radar can effectively penetrate fog, smoke and dust, and meet the requirements of all-time and all-weather working load. The millimeter-wave radar transmits a frequency-modulated continuous wave (FMCW) through an antenna, and a time difference exists between the received echo and the transmitted wave after reflection by a target. The target distance can be calculated by using the time difference. By analyzing the frequency difference between the transmitted and reflected signals through a signal processor, the motion speed of the target relative to the radar can be accurately measured based on the Doppler principle. Further, through a multi-target detection and tracking algorithm, multi-target separation and tracking can be realized.

[0003] In recent years, the installation of millimeter-wave radars in automobile auxiliary driving systems has rapidly increased. Main products include vehicle-mounted adaptive cruise control devices (ACC), front-end collision warning systems (FCW), auxiliary lane changing systems (LCA), automatic following systems (S&G), rear-end blind area detection devices (BSD), and lateral detection systems (CTA).

[0004] Since a common single millimeter-wave radar can only measure the relative radial motion speed and cannot measure the absolute motion speed direction of the target, when the included angle between the real motion direction of the target and the radial direction is large, if only the relative radial motion speed is used as the basis for judging the real motion speed of the target, a large speed measurement error will be caused. In addition, the measurement of the single millimeter-wave radar is easily affected by multipath effects, sidelobe scattering, and high-reflection stationary ground objects, which forms false obstacles and reduces the positioning accuracy of the target in the carrier coordinate system, thereby bringing great hidden dangers to driving safety. SUMMARY

[0005] In view of the above problems in the prior art, the present application provides a dual-millimeter-wave-radar fusion target detection method, a terminal device and a storage medium, which can effectively improve the accuracy of target point detection by filtering false alarms of millimeter-wave radars caused by multipath effects and clutter scattering through fusion of two measurements.

[0006] To achieve the above object, the present application provides a dual-millimeter-wave-radar fusion target detection method, which comprises the following steps:

[0007] The target detection method comprises the following steps:

[0008] Step 1: Acquire the first point cloud data frame collected by the first millimeter-wave radar and the second point cloud data frame collected by the second millimeter-wave radar at the same time frame. The first point cloud data frame contains a plurality of first point clouds, and the second point cloud data frame contains a plurality of second point clouds.

[0009] Step 2: Project all first point clouds from the spherical coordinate system of the first millimeter-wave radar to the spherical coordinate system of the second millimeter-wave radar to obtain a set of first point clouds composed of several first point clouds. The set of first point clouds has the point cloud information of each first point cloud in the spherical coordinate system of the first millimeter-wave radar and the point cloud information after being projected to the spherical coordinate system of the second millimeter-wave radar.

[0010] Step 3: Add the point cloud information of all the second point clouds to the second point cloud set;

[0011] Step 4: Associate and match the first point cloud set with the second point cloud set to obtain all associated and matched point cloud pairs and their point cloud information;

[0012] Step 5: Based on the point cloud information of each associated matching point cloud pair, obtain the optimal position and absolute velocity of the target corresponding to each associated matching point cloud pair in the carrier coordinate system.

[0013] In one embodiment, step 2 specifically includes:

[0014] Obtain the point cloud information of the first point cloud in the spherical coordinate system of the first millimeter-wave radar, for in, These represent the radial distance, radial relative velocity, vertical angle, and horizontal angle of the first point cloud i in the first millimeter-wave radar spherical coordinate system, respectively.

[0015] The radial relative velocity of the first point cloud i Updated to absolute radial velocity Then, the location information of the first point cloud. By projecting the spherical coordinate system of the first millimeter-wave radar onto the spherical coordinate system of the second millimeter-wave radar, we obtain... in, These represent the radial distance, vertical angle, and horizontal angle of the first point cloud i in the second millimeter-wave radar spherical coordinate system, respectively.

[0016] The point cloud information of the first point cloud i in each coordinate system Add to the first point cloud collection.

[0017] In one embodiment, the radial relative velocity of the first point cloud i Updated to absolute radial velocity Specifically:

[0018] For the first point cloud i, the carrier velocity V is converted and projected into the spherical coordinate system of the first millimeter wave radar through the relative coordinate relationship space, and a projected velocity is obtained The absolute radial velocity of the first point cloud i is

[0019] In one embodiment, the position information of the first point cloud is projected from the spherical coordinate system of the first millimeter wave radar to the spherical coordinate system of the second millimeter wave radar, specifically:

[0020] First, the position information of the first point cloud is transformed from the spherical coordinate system of the first millimeter wave radar to the Cartesian coordinate system of the first millimeter wave radar;

[0021] Second, the position information of the first point cloud is transformed from the Cartesian coordinate system of the first millimeter wave radar to the Cartesian coordinate system of the second millimeter wave radar;

[0022] Finally, the position information of the first point cloud is transformed from the Cartesian coordinate system of the second millimeter wave radar to the spherical coordinate system of the second millimeter wave radar.

[0023] In one embodiment, in step 3, the point cloud information of the second point cloud is Wherein, The absolute radial velocity, the radial distance, the vertical angle, and the horizontal angle of the second point cloud j in the spherical coordinate system of the second millimeter wave radar are respectively

[0024] The absolute radial velocity Wherein, The radial relative velocity of the second point cloud j in the spherical coordinate system of the second millimeter wave radar is The projected velocity of the carrier velocity V through the relative coordinate relationship space conversion and projection into the spherical coordinate system of the first millimeter wave radar.

[0025] In one embodiment, step 4 specifically includes:

[0026] The distance weight of each first point cloud in the first point cloud set and each second point cloud in the second point cloud set is calculated, and n R_l The weight matrix of n R_r rows and n R_l columns is obtained, wherein n R_r is the number of first point clouds in the first point cloud set, and n

[0027] Based on the weight matrix, the weighted Hungarian algorithm is used to obtain all the associated matching point cloud pairs in the first point cloud set and the second point cloud set.

[0028] In one embodiment, the distance weight of the first point cloud and the second point cloud is:​

[0029]

[0030] wherein w i,j is the distance weight of the first point cloud i and the second point cloud j, Thre is the limit coefficient, are respectively the radial distance weight, the vertical angle distance weight, the horizontal angle distance weight of the first point cloud i and the second point cloud j, and specifically:

[0031]

[0032]

[0033]

[0034] wherein σ r , σ ω , σ θ are respectively the distance accuracy, the vertical angle accuracy, the horizontal angle accuracy.

[0035] In one of the embodiments, in step 5, the optimal position of the target corresponding to each associated matching point cloud pair in the carrier coordinate system is specifically:

[0036] Suppose the target k corresponds to the associated matching point cloud C k is composed of the first point cloud i and the first point cloud j, that is:

[0037]

[0038] wherein represents the absolute radial velocity of the first point cloud i in the first millimeter wave radar spherical coordinate system, represents the vertical angle of the first point cloud i in the first millimeter wave radar spherical coordinate system, represents the horizontal angle of the first point cloud i in the first millimeter wave radar spherical coordinate system, represents the radial distance of the first point cloud i in the second millimeter wave radar spherical coordinate system, represents the vertical angle of the first point cloud i in the second millimeter wave radar spherical coordinate system, represents the horizontal angle of the first point cloud i in the second millimeter wave radar spherical coordinate system, represents the absolute radial velocity of the second point cloud j in the second millimeter wave radar spherical coordinate system, represents the radial distance of the second point cloud j in the second millimeter wave radar spherical coordinate system, represents the vertical angle of the second point cloud j in the second millimeter wave radar spherical coordinate system, represents the horizontal angle of the second point cloud j in the second millimeter wave radar spherical coordinate system.

[0039] calculating the optimal position of the target k in the second millimeter wave radar spherical coordinate system is:

[0040]

[0041] based on the optimal position of the target k in the second millimeter wave radar spherical coordinate system obtaining the optimal position of the target k in the second millimeter wave radar Cartesian coordinate system based on the optimal position of the target k in the second millimeter wave radar Cartesian coordinate system obtaining the optimal position P of the target k in the carrier coordinate system k .

[0042] In one of the embodiments, in step 5, the absolute motion speed of the target corresponding to each associated matched point cloud in the carrier coordinate system is specifically:

[0043] Let the radial vector of the target k in the first millimeter wave radar Cartesian coordinate system be then:

[0044]

[0045] Let the radial vector of the target k in the second millimeter wave radar Cartesian coordinate system be then:

[0046]

[0047] Let the absolute motion speed of the target k in the carrier coordinate system be wherein, is the absolute motion speed of the target k in the carrier coordinate system along the x-axis direction, is the absolute motion speed of the target k in the carrier coordinate system along the y-axis direction;

[0048] Project the absolute motion speed of the target k to the radial vector to obtain the projection speed is:

[0049]

[0050] Project the absolute motion speed of the target k to the radial vector to obtain the projection speed is:

[0051]

[0052] Let then the following equation can be established:

[0053]

[0054] Solving the above equation can obtain the value of and , that is, the absolute motion velocity V of the target k in the carrier coordinate system k .

[0055] In one of the embodiments, the first millimeter wave radar and the second millimeter wave radar are respectively carried on the left and right sides of the front end of the carrier.

[0056] To achieve the above object, the application further provides a terminal device, characterized by comprising:

[0057] a memory for storing a program;

[0058] a processor for executing the program stored in the memory, when the program is executed, the processor is used to execute part or all steps of the double millimeter wave radar fusion target detection method as described above.

[0059] To achieve the above object, the application further provides a computer readable storage medium, characterized by storing computer execution instructions in the computer readable storage medium; when the computer execution instructions are executed by the processor, part or all steps of the double millimeter wave radar fusion target detection method as described above are implemented.

[0060] Compared with the prior art, the application has the following beneficial technical effects:

[0061] 1. By obtaining the detection results of the double millimeter wave radars at the same time, and based on the coordinate system conversion, the detection results of the double millimeter wave radars are correlated and matched in the spherical coordinate system of any millimeter wave radar, so as to make them more conform to the scanning mode of the millimeter wave radar based on the polar coordinate;

[0062] 2. The distance weight between the point clouds is considered from the radial distance, the vertical angle distance and the horizontal angle distance, and in the process of positioning and velocity detection of the target, the matched point cloud pair is reserved as the real point cloud according to the distance weight between the point clouds, so as to effectively filter the false alarm of the millimeter wave radar caused by the multipath effect and the clutter scattering, and improve the accuracy of the target point detection;

[0063] 3. The absolute motion velocity size and direction of the target in the carrier coordinate system can be output, and the problem that the single millimeter wave radar can only measure the radial velocity and cannot solve the lateral target detection problem is solved. BRIEF DESCRIPTION OF DRAWINGS

[0064] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or prior art description. Obviously, the drawings in the following description only represent some of the embodiments of the present application, and for those skilled in the art, other drawings can also be obtained from the structures shown in these drawings without creative labor.

[0065] Figure 1 Flow chart of the double-millimeter-wave-radar fusion target detection method in the embodiments of the present application.

[0066] Figure 2 Detection target schematic diagram of the double-millimeter-wave-radar fusion target detection method in the embodiments of the present application.

[0067] Figure 3 Structure block diagram of the terminal device in the embodiments of the present application.

[0068] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0069] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0070] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the directional indications will also change accordingly.

[0071] In addition, the description such as "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0072] In the present application, unless otherwise explicitly specified and limited, the terms "connection", "fixing", and the like should be understood broadly, for example, "fixing" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection, or physical connection, or wireless communication connection; can be directly connected, or indirectly connected through an intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise explicitly limited. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0073] In addition, the technical solutions among various embodiments of the present application can be combined with each other, but it must be based on the fact that a person of ordinary skill in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the protection scope required by the present application.

[0074] The embodiment discloses a dual-millimeter-wave-radar fusion target detection method, which comprises the following steps: mounting a first millimeter-wave radar and a second millimeter-wave radar on a carrier, and the scanning areas of the first millimeter-wave radar and the second millimeter-wave radar are partially or wholly overlapped; acquiring point cloud data by the first millimeter-wave radar and the second millimeter-wave radar simultaneously; and measuring the absolute motion speed and direction of a target by means of two-frame point cloud data fusion, thereby improving the target detection precision and solving the problem that a single millimeter-wave radar can only measure radial speed and cannot solve the problem of lateral target detection. The carrier can be a vehicle or a robot, etc. In the specific implementation process, the first millimeter-wave radar and the second millimeter-wave radar are respectively mounted on the left and right sides of the front end of the carrier.

[0075] For the convenience of subsequent embodiments, the following definitions are made:

[0076] The carrier coordinate system is defined as

[0077] The first millimeter-wave radar is defined as R_l, and the Cartesian coordinate system of the first millimeter-wave radar R_l is defined as The spherical coordinate system of the first millimeter-wave radar R_l is defined as The rotation matrix of the first millimeter-wave radar R_l to the carrier coordinate system is The translation matrix is

[0078] The second millimeter-wave radar is defined as R_r, and the Cartesian coordinate system of the second millimeter-wave radar R_r is defined as The spherical coordinate system of the second millimeter-wave radar R_r is defined as The rotation matrix of the second millimeter-wave radar R_r to the carrier coordinate system is The translation matrix is

[0079] refer to Figures 1-2 The target detection method in this embodiment specifically includes the following steps 1-4.

[0080] Step 1: Acquire the first point cloud data frame collected by the first millimeter-wave radar and the second point cloud data frame collected by the second millimeter-wave radar at the same time frame.

[0081] The first point cloud data frame contains a number of first point clouds. In this embodiment, the number of first point clouds in the first point cloud data frame is defined as n. R_l For a given first point cloud i, its partial output information in the first point cloud data frame can be represented as follows: in, Let the first point cloud i be in spherical coordinates. Radial distance below, Let the first point cloud i be in spherical coordinates. Radial relative velocity below, Let the first point cloud i be in spherical coordinates. The vertical angle below, Let the first point cloud i be in spherical coordinates. The horizontal angle below.

[0082] The second point cloud data frame contains a number of second point clouds. In this embodiment, the number of second point clouds in the second point cloud data frame is defined as n. R_r For a given second point cloud j, its partial output information in the second point cloud data frame can be represented as follows: in, Let the second point cloud j be in spherical coordinates. Radial distance below, Let the second point cloud j be in spherical coordinates. Radial relative velocity below, Let the second point cloud j be in spherical coordinates. The vertical angle below, Let the second point cloud j be in spherical coordinates. The horizontal angle below.

[0083] Step 2: Project all first point clouds from the spherical coordinate system of the first millimeter-wave radar to the spherical coordinate system of the second millimeter-wave radar to obtain a set of first point clouds composed of several first point clouds. The set of first point clouds contains the point cloud information of each first point cloud in the first millimeter-wave radar spherical coordinate system and the point cloud information after projection onto the second millimeter-wave radar spherical coordinate system. The specific implementation process is as follows:

[0084] Step 2.1, obtain the first point cloud i in spherical coordinate system Point cloud information

[0085] Step 2.2, the radial relative velocity of the first point cloud i is updated to absolute radial velocity Step 2.3, the position information of the first point cloud i in the spherical coordinate system is defined as For the first point cloud i, the carrier velocity V is converted and projected to the spherical coordinate system through the relative coordinate relationship in space , and the projected velocity is Further, the absolute radial velocity of the first point cloud i is

[0086] Step 2.3, the position information of the first point cloud i in the spherical coordinate system is defined as Step 2.4, based on the processing results of step 2.2 and step 2.3, the output information of the first point cloud i in each coordinate system is represented as First, the position information of the first point cloud i is converted from the spherical coordinate system to the Cartesian coordinate system , and the position information of the first point cloud i in the Cartesian coordinate system is obtained . Then, the position information of the first point cloud i is converted from the Cartesian coordinate system to the Cartesian coordinate system , and the position information of the first point cloud i in the Cartesian coordinate system is obtained . Finally, the position information of the first point cloud i is converted from the Cartesian coordinate system to the spherical coordinate system , and the position information of the first point cloud i in the spherical coordinate system is obtained . wherein is the radial distance of the first point cloud i in the spherical coordinate system , is the vertical angle of the first point cloud i in the spherical coordinate system , is the horizontal angle of the first point cloud i in the spherical coordinate system ;

[0087] Step 2.4, based on the processing results of step 2.2 and step 2.3, the output information of the first point cloud i in each coordinate system is represented as Then is added to the first point cloud set M R_l ;

[0088] Step 2.5, steps 2.1-2.4 are performed on all first point clouds, i.e. the first point cloud set M with the point cloud information of all first point clouds in the spherical coordinate system and the point cloud information after projection to the coordinate system R_l.

[0089] Step 3, add the point cloud information of all second point clouds to the second point cloud set, the specific implementation process is as follows:

[0090] Step 3.1, obtain the point cloud information of the second point cloud j in the spherical coordinate system

[0091] Step 3.2, update the radial relative velocity of the second point cloud j to the absolute radial velocity For the second point cloud j, the carrier velocity V is converted and projected into the spherical coordinate system through the relative coordinate relationship, and the projected velocity is Further, the absolute radial velocity of the second point cloud j can be obtained as

[0092] Step 3.3, based on the processing result of step 3.2, the output information of the second point cloud j in each coordinate system is obtained and represented as Further, the is added to the second point cloud set M R_r ;

[0093] Step 3.4, perform steps 2.1-2.3 on all second point clouds, that is, the second point cloud set M with the point cloud information of all second point clouds is obtained R_r .

[0094] Step 4, associate and match the first point cloud set and the second point cloud set to obtain all associated and matched point cloud pairs and their point cloud information, the specific implementation process is as follows:

[0095] Step 4.1, calculate the distance weight of each first point cloud in the first point cloud set and each second point cloud in the second point cloud set, to obtain an n R_l row n R_r column weight matrix W, wherein the distance weight of the first point cloud and the second point cloud is:

[0096]

[0097] In the formula, w i,j is the distance weight of the first point cloud i and the second point cloud j, Thre is the limit coefficient, and in the embodiment, the limit coefficient Thre is set to 0.2;

[0098] , respectively, are the radial distance weight, the vertical angle distance weight and the horizontal angle distance weight of the first point cloud i and the second point cloud j, and the calculation processes are as follows:

[0099] ​

[0100]

[0101]

[0102] wherein σ r is the distance accuracy of the first and second millimeter wave radars, σ ω is the vertical angle accuracy of the first and second millimeter wave radars, σ θ is the horizontal angle accuracy of the first and second millimeter wave radars.

[0103] Step 4.2, based on the weight matrix W calculated in step 4.1, using a weighted Hungarian algorithm (Kuhn-Munkras algorithm) to obtain all the associated matching point cloud pairs in the first point cloud set M R_l and the second point cloud set M R_r .

[0104] Step 5, based on the point cloud information of each associated matching point cloud pair, obtaining the optimal position and absolute motion velocity of the target corresponding to each associated matching point cloud pair in the carrier coordinate system.

[0105] Let the associated matching point cloud C k corresponding to target k be composed of the first point cloud i and the first point cloud j, that is:

[0106]

[0107] wherein represents the absolute radial velocity of the first point cloud i in the spherical coordinate system , represents the vertical angle of the first point cloud i in the spherical coordinate system , represents the horizontal angle of the first point cloud i in the spherical coordinate system , represents the radial distance of the first point cloud i in the spherical coordinate system , represents the vertical angle of the first point cloud i in the spherical coordinate system , represents the horizontal angle of the first point cloud i in the spherical coordinate system , represents the absolute radial velocity of the second point cloud j in the spherical coordinate system , represents the radial distance of the second point cloud j in the spherical coordinate system , represents the vertical angle of the second point cloud j in the spherical coordinate system , represents the horizontal angle of the second point cloud j in the spherical coordinate system .

[0108] The optimal position of the target k in the spherical coordinate system is calculated as

[0109]

[0110] Based on the optimal position of the target k in the spherical coordinate system , the optimal position of the target k in the Cartesian coordinate system defined as is obtained as Based on the optimal position of the target k in the Cartesian coordinate system defined as , the optimal position of the target k in the carrier coordinate system is obtained as wherein are the optimal positions of the target k in the x, y, z axes of the carrier coordinate system , respectively.

[0111] Let the radial vector of the target k in the Cartesian coordinate system defined as be then we have

[0112]

[0113] Let the radial vector of the target k in the Cartesian coordinate system defined as be then we have

[0114]

[0115] Let the absolute motion velocity of the target k in the carrier coordinate system be wherein is the absolute motion velocity of the target k in the x-axis direction of the carrier coordinate system , and is the absolute motion velocity of the target k in the y-axis direction of the carrier coordinate system .

[0116] The absolute motion velocity of the target k is projected onto the radial vector , and the projection velocity is obtained as

[0117]

[0118] The absolute motion velocity of the target k is projected onto the radial vector​​​​ The projection is obtained, and the projection velocity is

[0119]

[0120] Let Then the following equation can be established:

[0121]

[0122] Let The above equation can be expressed as: The least square method is used to solve The values of and can be obtained, that is, the absolute motion velocity V k of the target k in the carrier coordinate system is obtained.

[0123] With reference to Figure 3 , the embodiment further provides a terminal device including a transmitter, a receiver, a memory and a processor. The transmitter is configured to transmit instructions and data, the receiver is configured to receive instructions and data, the memory is configured to store computer execution instructions, and the processor is configured to execute the computer execution instructions stored in the memory to implement each step of the double-millimeter-wave-radar-fusion target detection method performed by the terminal device. The specific implementation process is the same as that of the double-millimeter-wave-radar-fusion target detection method.

[0124] It should be noted that the memory can be independent or integrated with the processor. When the memory is independently arranged, the terminal device further includes a bus for connecting the memory and the processor.

[0125] The embodiment further provides a computer readable storage medium, and the computer readable storage medium stores computer execution instructions. When the processor executes the computer execution instructions, the double-millimeter-wave-radar-fusion target detection method performed by the terminal device is implemented.

[0126] The above only describes the preferred embodiments of the present application, and does not limit the patent scope of the present application. Any equivalent structural transformation made according to the content of the present application specification and drawings, or direct / indirect application in other related technical fields is included in the patent protection scope of the present application.​

Claims

1. A dual-millimeter wave radar fusion target detection method, characterized in that, A first millimeter-wave radar and a second millimeter-wave radar are mounted on a carrier, and the scanning areas of the first millimeter-wave radar and the second millimeter-wave radar partially or completely overlap. The target detection method includes the following steps: Step 1: Acquire the first point cloud data frame collected by the first millimeter-wave radar and the second point cloud data frame collected by the second millimeter-wave radar at the same time frame. The first point cloud data frame contains a plurality of first point clouds, and the second point cloud data frame contains a plurality of second point clouds. Step 2: Project all first point clouds from the spherical coordinate system of the first millimeter-wave radar to the spherical coordinate system of the second millimeter-wave radar to obtain a set of first point clouds composed of several first point clouds. The set of first point clouds has the point cloud information of each first point cloud in the spherical coordinate system of the first millimeter-wave radar and the point cloud information after being projected to the spherical coordinate system of the second millimeter-wave radar. Step 3: Add the point cloud information of all the second point clouds to the second point cloud set; Step 4: Associate and match the first point cloud set with the second point cloud set to obtain all associated and matched point cloud pairs and their point cloud information, specifically including: calculate a distance weight of each first point cloud in the first point cloud set and each second point cloud in the second point cloud set, to obtain a weight matrix of rows and columns, wherein, is a number of the first point cloud in the first point cloud set, is a number of the second point cloud in the second point cloud set; Based on the weight matrix, the weighted Hungarian algorithm is used to obtain all associated matching point cloud pairs in the first point cloud set and the second point cloud set; Step 5: Based on the point cloud information of each associated matching point cloud pair, obtain the optimal position and absolute velocity of the target corresponding to each associated matching point cloud pair in the carrier coordinate system.

2. The dual-millimeter wave radar fusion target detection method of claim 1, wherein, Step 2 specifically includes: The point cloud information of the first point cloud in the spherical coordinate system of the first millimeter wave radar is obtained, that is, wherein, respectively, the first point cloud The radial distance, the radial relative speed, the vertical angle, and the horizontal angle in the spherical coordinate system of the first millimeter wave radar. The first point cloud radial relative velocity Updated to absolute radial velocity Then, the location information of the first point cloud. By projecting the spherical coordinate system of the first millimeter-wave radar onto the spherical coordinate system of the second millimeter-wave radar, we obtain... ,in, The first point cloud Radial distance, vertical angle, and horizontal angle in the second millimeter-wave radar spherical coordinate system; adding the first point cloud point cloud information in each coordinate system to the first point cloud set.

3. The dual millimeter-wave radar fusion target detection method according to claim 2, characterized in that, The first point cloud The radial relative velocity The absolute radial velocity Specifically: For the first point cloud The carrier velocity By the relative coordinate relationship space conversion and projection into the spherical coordinate system of the first millimeter wave radar, the projected velocity is obtained Then the first point cloud The absolute radial velocity of the first point cloud 4. The dual millimeter-wave radar fusion target detection method according to claim 2, characterized in that, The location information of the first point cloud The projection from the spherical coordinate system of the first millimeter-wave radar to the spherical coordinate system of the second millimeter-wave radar is as follows: First, the position information of the first point cloud is transformed from the spherical coordinate system of the first millimeter-wave radar to the Cartesian coordinate system of the first millimeter-wave radar; Secondly, the position information of the first point cloud is transformed from the Cartesian coordinate system of the first millimeter-wave radar to the Cartesian coordinate system of the second millimeter-wave radar; Finally, the position information of the first point cloud is transformed from the Cartesian coordinate system of the second millimeter-wave radar to the spherical coordinate system of the second millimeter-wave radar.

5. The dual millimeter-wave radar fusion target detection method according to any one of claims 1 to 4, characterized in that, In step 3, the point cloud information of the second point cloud is wherein, is the second point cloud absolute radial velocity, radial distance, vertical angle, horizontal angle in the second millimeter wave radar spherical coordinate system absolute radial velocity wherein, is a second point cloud a radial relative velocity in a second millimeter wave radar spherical coordinate system, is a carrier velocity a projected velocity after spatial conversion by relative coordinate relationship and projection to the spherical coordinate system of the first millimeter wave radar.

6. The dual-millimeter wave radar fusion target detection method according to any one of claims 1 to 4, characterized in that, The distance weights between the first and second point clouds are: In the formula, is the first point cloud is the distance weight of the second point cloud , is the limiting coefficient, is the radial distance weight of the first point cloud is the vertical angle distance weight of the second point cloud is the horizontal angle distance weight of the second point cloud, specifically: In the formula, respectively, the first point cloud The radial distance, the vertical angle, and the horizontal angle in the second millimeter wave radar spherical coordinate system, respectively, the second point cloud The absolute radial velocity, the radial distance, the vertical angle, and the horizontal angle in the second millimeter wave radar spherical coordinate system, respectively, the distance accuracy, the vertical angle accuracy, and the horizontal angle accuracy.

7. The dual-millimeter wave radar fusion object detection method according to any one of claims 1 to 4, characterized in that, In step 5, the optimal position of the target corresponding to each associated matching point cloud pair in the carrier coordinate system is as follows: Set goals The corresponding associated matching point cloud By the first point cloud With the first point cloud Composition, namely: wherein represents the first point cloud absolute radial velocity in the first millimeter wave radar spherical coordinate system, represents the first point cloud vertical angle angle in the first millimeter wave radar spherical coordinate system, represents the first point cloud horizontal angle angle in the first millimeter wave radar spherical coordinate system, represents the first point cloud radial distance in the second millimeter wave radar spherical coordinate system, represents the first point cloud vertical angle angle in the second millimeter wave radar spherical coordinate system, represents the first point cloud horizontal angle angle in the second millimeter wave radar spherical coordinate system, represents the second point cloud absolute radial velocity in the second millimeter wave radar spherical coordinate system, represents the second point cloud radial distance in the second millimeter wave radar spherical coordinate system, represents the second point cloud vertical angle angle in the second millimeter wave radar spherical coordinate system, represents the second point cloud horizontal angle angle in the second millimeter wave radar spherical coordinate system; Computing target Optimal position in a second millimeter wave radar spherical coordinate system To: Based on target Optimal position in the second millimeter wave radar spherical coordinate system , get target Optimal position in the second millimeter wave radar Cartesian coordinate system , based on target Optimal position in the second millimeter wave radar Cartesian coordinate system Get target Optimal position in the carrier coordinate system .

8. The dual-millimeter wave radar fusion target detection method of claim 7, wherein, In step 5, the absolute motion velocity of the target corresponding to each associated matching point cloud pair in the carrier coordinate system is as follows: Set goals The radial vector in the first millimeter wave radar Cartesian coordinate system is Then, we have: Set goals The radial vector in the second millimeter wave radar Cartesian coordinate system is Then, we have: Remember the goal absolute motion velocity in the carrier coordinate system wherein, Remember the goal absolute motion velocity in the carrier coordinate system in the direction of the axis, Remember the goal absolute motion velocity in the carrier coordinate system in the direction of the axis; The objective is to determine the absolute motion velocity of the target by projecting the radial vector onto the velocity vector The objective absolute motion velocity radial vector projection, the projection velocity is : Let , , the following equation is established: Solving the above equations gives the values of and , i.e. the target In the carrier coordinate system, the absolute motion velocity .

9. A terminal device, comprising: include: Memory, used to store programs; A processor is configured to execute the program stored in the memory, and when the program is executed, the processor is configured to perform some or all of the steps of the dual millimeter-wave radar fusion target detection method as described in any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions; when executed by a processor, the computer-executable instructions are used to implement some or all of the steps of the dual millimeter-wave radar fusion target detection method as described in any one of claims 1 to 8.

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