Millimeter wave radar antenna array amplitude and phase calibration method and apparatus

Abstract

Embodiments of the present application provide a millimeter wave radar antenna array amplitude and phase calibration method and device, relating to the technical field of radar, the method comprising: constructing a target phase difference model based on a target near-field calibration environment; determining a target amplitude and phase factor according to the target phase difference model and target amplitude and phase information; and performing a target amplitude and phase calibration operation according to the target amplitude and phase factor. In this way, precise amplitude and phase calibration operations can be performed on the millimeter wave radar antenna array without relying on far-field conditions, which is beneficial to reducing the cost of millimeter wave radar antenna array amplitude and phase calibration and improving the efficiency of millimeter wave radar antenna array amplitude and phase calibration.

Description

TECHNICAL FIELD

[0001] Embodiments of the present application relate to the technical field of radar, and in particular, to a millimeter wave radar antenna array amplitude and phase calibration method and device. BACKGROUND

[0002] At present, millimeter wave radars have been widely used in automatic driving, intelligent sensing, security monitoring, medical imaging and other fields due to their high resolution, strong anti-interference ability, good penetration and other advantages.

[0003] In related technologies, millimeter wave radar antenna array amplitude and phase calibration mostly relies on far field conditions, and the above method leads to high cost and low efficiency in the millimeter wave radar antenna array amplitude and phase calibration process. SUMMARY

[0004] According to embodiments of the present application, a millimeter wave radar antenna array amplitude and phase calibration method and device are provided, which can perform high-precision amplitude and phase calibration operation on the millimeter wave radar antenna array without relying on far field conditions, thereby reducing the cost of millimeter wave radar antenna array amplitude and phase calibration and improving the efficiency of millimeter wave radar antenna array amplitude and phase calibration.

[0005] In a first aspect of the present application, a millimeter wave radar antenna array amplitude and phase calibration method is provided, which is suitable for a near field environment, and includes:

[0006] Based on the target near field calibration environment, a target phase difference model is constructed;

[0007] According to the target phase difference model and the target amplitude and phase information, a target amplitude and phase factor is determined;

[0008] According to the target amplitude and phase factor, a target amplitude and phase calibration operation is performed.

[0009] In some possible implementations, the above method of constructing a target phase difference model based on a target near field calibration environment includes:

[0010] Based on the target near field calibration environment, a target physical distance is calculated;

[0011] According to the target physical distance, a target phase difference model is constructed.

[0012] In some possible implementations, the above method of calculating a target physical distance based on a target near field calibration environment includes:

[0013] The first physical distance is determined according to the following formula:

[0014]

[0015] The second physical distance is determined according to the following formula:

[0016]

[0017] wherein, is used to represent the first physical distance; is used to represent the first target transmitting antenna in the first reference coordinate axis direction; is used to represent the first target transmitting antenna in the third reference coordinate axis direction; is used to represent the second physical distance; is used to represent the first target receiving antenna in the first reference coordinate axis direction; is used to represent the first target receiving antenna in the third reference coordinate axis direction; is used to represent the first reference target distance; is used to represent the second reference target distance; is used to represent the third reference target distance.

[0018] In some possible implementations, the above constructing the target phase difference model according to the target physical distance comprises:

[0019] determining the target phase difference according to the first physical distance and the second physical distance;

[0020] constructing the target phase difference model according to the target phase difference.

[0021] In some possible implementations, the above method further comprises:

[0022] determining the target phase difference according to the following formula:

[0023]

[0024] wherein, is used to represent the target phase difference; is used to represent the second target transmitting antenna corresponding first physical distance; is used to represent the second target receiving antenna corresponding second physical distance; is used to represent the working wavelength of the millimeter wave radar to be calibrated.

[0025] In some possible implementations, the above determining the target amplitude and phase factor according to the target phase difference model and the target amplitude and phase information comprises:

[0026] The target amplitude-phase factor is determined using the following formula:

[0027]

[0028] in, Used to represent the target amplitude-phase factor; Used to indicate the transmitting antenna of the second target Second target receiving antenna Corresponding amplitude and phase information; Used to indicate the transmitting antenna of the first target and the first target receiving antenna Corresponding amplitude and phase information; Used to represent the imaginary unit.

[0029] In some feasible implementations, the above method further includes:

[0030] The target amplitude-phase factor is compensated according to the following formula:

[0031]

[0032] in, Used to indicate the transmitting antenna of the first target and the first target receiving antenna The corresponding complex value of the target detection point after correction; Used to indicate the transmitting antenna of the first target and the first target receiving antenna The complex value of the corresponding target detection point.

[0033] In some feasible implementations, the above method further includes:

[0034] Based on the target distance index and / or the target Doppler index, extract and generate target amplitude and phase information.

[0035] In some feasible implementations, the above method further includes:

[0036] The target distance index is determined using the following formula:

[0037]

[0038] in, Used to represent the target distance index; Used to indicate the target number of sampling points; Used to represent the target frequency modulation slope; Used to represent the speed of light; Used to represent the target sampling rate.

[0039] A second aspect of this application provides a millimeter-wave radar antenna array amplitude and phase calibration device, applicable to the method described above, comprising:

[0040] The building unit is used to construct a target phase difference model based on the target near-field calibration environment;

[0041] The determining unit is used to determine the target amplitude and phase factor based on the target phase difference model and target amplitude and phase information;

[0042] The execution unit is used to perform target amplitude and phase calibration operations based on the target amplitude and phase factor.

[0043] The millimeter-wave radar antenna array amplitude and phase calibration method and apparatus provided in this application are applicable to near-field environments. The method includes: constructing a target phase difference model based on the target near-field calibration environment; determining the target amplitude and phase factor based on the target phase difference model and target amplitude and phase information; and performing target amplitude and phase calibration operations based on the target amplitude and phase factor. In this way, accurate amplitude and phase calibration operations can be performed on millimeter-wave radar antenna arrays without relying on far-field conditions, which helps to reduce the cost and improve the efficiency of millimeter-wave radar antenna array amplitude and phase calibration.

[0044] It should be understood that the description in the Summary Section is not intended to limit the key or essential features of the embodiments of this application, nor is it intended to restrict the scope of this application. Other features of this application will become readily apparent from the following description. Attached Figure Description

[0045] The above and other features, advantages, and aspects of the embodiments of this application will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0046] Figure 1 A flowchart illustrating a millimeter-wave radar antenna array amplitude and phase calibration method provided in this application embodiment;

[0047] Figure 2 A schematic diagram of a target Cartesian coordinate system corresponding to a target near-field calibration environment provided in this application embodiment;

[0048] Figure 3 A schematic diagram of an angular-dimensional spectrum provided in an embodiment of this application;

[0049] Figure 4 This is another angular dimensional spectrum diagram provided in the embodiments of this application;

[0050] Figure 5 This is yet another angular-dimensional spectrum diagram provided in the embodiments of this application;

[0051] Figure 6 This is yet another angular-dimensional spectrum diagram provided in the embodiments of this application;

[0052] Figure 7 A structural schematic diagram of a millimeter-wave radar antenna array calibration device provided in this application embodiment;

[0053] Figure 8 This is a structural schematic diagram of an electronic device provided in an embodiment of this application. Detailed Implementation

[0054] To make the objectives, technical solutions, and advantages of the embodiments of this disclosure clearer, the technical solutions of the embodiments of this disclosure will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0055] Furthermore, the term "and / or" in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0056] Currently, millimeter-wave radar is widely used in fields such as autonomous driving, intelligent sensing, security monitoring, and medical imaging due to its advantages such as high resolution, strong anti-interference capability, and good penetration. As application scenarios demand higher target recognition accuracy, millimeter-wave radar continues to develop towards higher resolution, and one of the core ways to improve resolution is to increase the aperture of the antenna array.

[0057] However, in radar systems, increasing the antenna aperture leads to increased amplitude and phase errors in the antenna array, resulting in beam pointing deviation, increased sidelobe levels, and deterioration of radar performance.

[0058] Therefore, amplitude and phase calibration of the radar antenna array is a key step in ensuring the accuracy of the radar system.

[0059] On the one hand, traditional calibration methods are based on far-field conditions, and their core principle is: when the calibration distance meets the far-field conditions (i.e.) ,in, Used to indicate calibration distance; Used to indicate antenna aperture; The electromagnetic waves incident on the antenna array (used to represent the operating wavelength) can be approximated as plane waves. In this case, errors can be directly extracted and compensated by measuring the amplitude and phase characteristics of the received or transmitted signals of each array element. However, the far-field calibration of high-resolution millimeter-wave radar needs to be performed at distances of tens or even hundreds of meters. For example, for an 80 GHz millimeter-wave traffic radar, when a 0.5° angular resolution is required, the antenna aperture needs to be increased to 0.43 m, resulting in a far-field distance of 98.6 m. Meanwhile, to avoid the influence of ground reflection, multipath effects, and environmental electromagnetic interference on calibration accuracy, far-field calibration usually needs to be carried out in a microwave anechoic chamber. However, constructing a microwave anechoic chamber tens of meters in size requires laying a large amount of absorbing material and occupies a large area, leading to high costs for the amplitude and phase calibration process of millimeter-wave radar antenna arrays. Furthermore, due to limitations in actual site conditions, most enterprises and research institutions lack the resources for such a large-scale anechoic chamber, severely restricting the practical application of traditional far-field calibration methods.

[0060] On the other hand, most existing near-field calibration methods acquire near-field amplitude and phase data of the antenna array through near-field scanning, and then reconstruct far-field characteristics based on near-field-to-far-field transformation algorithms, such as the plane wave spectrum method and the spherical wave expansion method, to achieve amplitude and phase error calibration. However, the above methods have the following drawbacks: First, the near-field-to-far-field transformation process is complex and requires precise knowledge of parameters such as the scanning probe position and array attitude, which places extremely high demands on the accuracy of the test system; Second, numerical errors are easily introduced during the transformation process, and the calibration results are sensitive to the algorithm model, resulting in insufficient calibration accuracy and failing to meet the stringent requirements of high-resolution millimeter-wave radar for amplitude and phase consistency; Third, the calibration process is cumbersome, requiring multi-point scanning and long-term data processing, which is inefficient and difficult to apply to engineering-scale batch calibration scenarios.

[0061] Therefore, in a first aspect of this application, a method for amplitude and phase calibration of a millimeter-wave radar antenna array is proposed, which aims to achieve high-precision amplitude and phase calibration of the millimeter-wave radar antenna array without relying on far-field conditions, thereby reducing the cost of amplitude and phase calibration of the millimeter-wave radar antenna array and improving the efficiency of amplitude and phase calibration of the millimeter-wave radar antenna array.

[0062] A first aspect of this application proposes a millimeter-wave radar antenna array amplitude and phase calibration method, suitable for near-field environments (i.e., ,in, Used to indicate calibration distance; Used to indicate antenna aperture; (Used to indicate the operating wavelength). Figure 1 This is a flowchart illustrating a millimeter-wave radar antenna array amplitude and phase calibration method 100 provided in an embodiment of this application, as shown below. Figure 1 As shown, method 100 includes:

[0063] Step S1: Construct a target phase difference model based on the target near-field calibration environment.

[0064] For example, the above-mentioned target near-field calibration environment can be constructed based on the following method: the millimeter-wave radar to be calibrated is fixedly installed; the center of the millimeter-wave radar to be calibrated is taken as the origin. O Establish the first reference coordinate axis along the horizontal direction, that is Axis; along the axis perpendicular to the first reference coordinate axis, i.e. Establish a second reference coordinate axis in the axial direction, that is Axis; along the first reference coordinate axis, i.e. The axis and the second reference coordinate axis are also The shaft constitutes xOy Establish a third reference coordinate axis in the perpendicular direction of the plane, that is... Axis; where the origin is... O , axis, shaft and The axes together constitute the target Cartesian coordinate system. O-xyz; The reference target is pre-set in the aforementioned Cartesian coordinate system. O-xyz The preset position in the target; wherein, the reference target is in the aforementioned target Cartesian coordinate system. O-xyz The coordinates in can be represented as ( , , The aforementioned reference target may correspond to a corner reflector, a metal sphere, and / or a simulated point target generated by a simulator, with a preset radar cross section (RCS), so that the aforementioned reference target is as close as possible to the ideal scattering point.

[0065] Specifically, when the aperture of the millimeter-wave radar array to be calibrated corresponds to 0.2m and the far-field condition corresponds to 20.5m at 80G, the above-mentioned near-field calibration environment for the target may include a microwave anechoic chamber with a length of 3.5m.

[0066] For example, the millimeter-wave radar to be calibrated can be fixed on an optical platform or a dedicated bracket in the aforementioned microwave anechoic chamber to ensure that the radar's attitude remains constant during calibration, and that both the transmitter and receiver are in normal working order. Figure 2 As shown, the origin is the center of the millimeter-wave radar to be calibrated. O This constitutes the aforementioned target Cartesian coordinate system. O-xyz; In the target Cartesian coordinate system O-xyz The second reference coordinate axis is also The axis coordinates are A metal sphere with a radar cross section (RCS) is placed at a location to serve as a reference target, thereby constructing a near-field calibration environment for the aforementioned target. The coordinates of the reference target correspond to... Among them, the above The value can be 3.5m.

[0067] In some feasible implementations, step S1 above; constructing a target phase difference model based on the target near-field calibration environment, includes:

[0068] Step S11: Calculate the physical distance to the target based on the target's near-field calibration environment.

[0069] It should be noted that the above-mentioned target physical distance corresponds to the physical distance of the above-mentioned reference target relative to each antenna array element.

[0070] In some feasible implementations, step S11 above; calculating the target physical distance based on the target near-field calibration environment, includes:

[0071] Step S111; Determine the first physical distance according to the following formula:

[0072] (1)

[0073] Step S112; Determine the second physical distance according to the following formula:

[0074] (2)

[0075] in, Used to indicate the first physical distance; Used to indicate the transmitting antenna of the first target First reference coordinate axis The coordinate components of the direction; Used to indicate the transmitting antenna of the first target On the third reference coordinate axis The coordinate components of the direction; Used to indicate the second physical distance; Used to indicate the first target receiving antenna First reference coordinate axis The coordinate components of the direction; Used to indicate the first target receiving antenna On the third reference coordinate axis The coordinate components of the direction; Used to indicate the distance to the first reference target; Used to indicate the distance to the second reference target; Used to indicate the distance to the third benchmark target; The index used to represent the transmitting antenna of the first target has the following value range: , The index used to represent the receiving antenna of the first target has the following value range: .

[0076] It is understandable that the aforementioned first benchmark target distance Corresponding to the above-mentioned reference target in the above-mentioned target Cartesian coordinate system O-xyz Mid-axis of the first reference coordinate axis The coordinate components of the direction, the distance to the second reference target mentioned above Corresponding to the above-mentioned reference target in the above-mentioned target Cartesian coordinate system O-xyz Mid-line of the second reference coordinate axis The coordinate components of the direction, the distance to the third reference target mentioned above Corresponding to the above-mentioned reference target in the above-mentioned target Cartesian coordinate system O-xyz Middle along the third reference coordinate axis The coordinate components of the direction.

[0077] Step S12: Construct a target phase difference model based on the target physical distance.

[0078] In some feasible implementations, step S12 above; constructing a target phase difference model based on the target physical distance, includes:

[0079] Step S121: Determine the target phase difference based on the first physical distance and the second physical distance.

[0080] In some feasible implementations, the above method further includes:

[0081] Step S1211; Determine the target phase difference according to the following formula:

[0082] (3)

[0083] in, Used to represent the target phase difference; Used to indicate the transmitting antenna of the second target The corresponding first physical distance; Used to indicate the second target receiving antenna The corresponding second physical distance; Used to indicate the operating wavelength of the millimeter-wave radar to be calibrated; The index used to represent the transmitting antenna of the second target is an integer greater than or equal to 1 and less than or equal to M. The index used to represent the second target receiving antenna is an integer greater than or equal to 1 and less than or equal to N.

[0084] It should be noted that the aforementioned target phase difference It can correspond to the first target transmitting antenna and the first target receiving antenna The virtual antenna formed relative to the second target transmitting antenna Second target receiving antenna The phase difference of the formed virtual antenna.

[0085] For example, the aforementioned second target transmitting antenna The corresponding first physical distance That is, the second target transmitting antenna The distance relative to the aforementioned benchmark target can be determined using the following formula:

[0086] (4)

[0087] in, Used to indicate the transmitting antenna of the second target First reference coordinate axis The coordinate components of the direction; Used to indicate the transmitting antenna of the second target On the third reference coordinate axis The coordinate components of the direction.

[0088] For example, the aforementioned second target receiving antenna The corresponding second physical distance That is, the second target receiving antenna The distance relative to the aforementioned benchmark target can be determined using the following formula:

[0089] (5)

[0090] in, Indicates the second target receiving antenna First reference coordinate axis The coordinate components of the direction; Used to indicate the second target receiving antenna Third reference coordinate axis The coordinate components of the direction.

[0091] Step S122: Construct a target phase difference model based on the target phase difference.

[0092] It should be noted that the target phase difference model described above can correspond to the relative phase difference model of each transceiver virtual array.

[0093] Step S2: Determine the target amplitude-phase factor based on the target phase difference model and target amplitude-phase information.

[0094] For example, the target amplitude and phase information can be determined by controlling each target transmitting antenna of the millimeter-wave radar to be calibrated to transmit signals to the reference target, wherein the target transmitted signals may include: a target quadrature modulated linear frequency modulated continuous wave (FMCW) signal. Each target receiving antenna is controlled to receive the corresponding target echo signal, and the target echo signal is mixed with the target transmitted signal to obtain the target difference frequency signal.

[0095] For example, target processing operations can be performed on the data corresponding to the aforementioned target difference frequency signal to extract the measured amplitude and phase data of different target transmitting or receiving antennas corresponding to the aforementioned reference target. The aforementioned target processing operations may include: 2D Fast Fourier Transform.

[0096] For example, a 2D Fast Fourier Transform can be performed on the above target echo data to obtain target two-dimensional spectrum data corresponding to different target receiving antennas for different target transmitting antennas.

[0097] In some feasible implementations, the above method further includes:

[0098] Based on the target distance index and / or the target Doppler index, extract and generate target amplitude and phase information.

[0099] For example, the target distance index and / or target Doppler index of the aforementioned reference target in the aforementioned target two-dimensional spectrum data can be calculated to extract the aforementioned generated target amplitude and phase information.

[0100] In some feasible implementations, the above method further includes:

[0101] The target distance index is determined using the following formula:

[0102] (6)

[0103] in, Used to represent the target distance index; Used to indicate the target number of sampling points; Used to represent the target frequency modulation slope; Used to represent the speed of light; Used to represent the target sampling rate.

[0104] It should be noted that the above target distance index This can correspond to the distance index of the aforementioned benchmark target; the aforementioned target Doppler index. The value of can be 1. The above target frequency modulation slope is the target frequency modulation slope. It can correspond to the frequency modulation slope of a target quadrature modulated linear frequency modulated continuous wave (FMCW) signal.

[0105] For example, the target distance index can be used as described above. And / or, target Doppler index Extract the amplitude and phase data corresponding to different target transmitting antennas and target receiving antennas corresponding to the reference target from the above two-dimensional spectrum data, and then use the first target transmitting antenna... and the first target receiving antenna The corresponding amplitude and phase information is represented as ,in, , The second target transmitting antenna Second target receiving antenna The corresponding amplitude and phase information is represented as .

[0106] In some feasible implementations, the above method further includes:

[0107] The distance to the second benchmark target is determined using the following formula. :

[0108] (7)

[0109] in, Used to indicate the target number of sampling points; Used to represent the target frequency modulation slope; Used to represent the speed of light; Used to represent the target sampling rate.

[0110] It should be noted that although this application is applicable to near-field environments, it does not mean that the distance between the above-mentioned reference target and the millimeter-wave radar to be calibrated can be arbitrarily small. Determining the distance of the second reference target based on the above formula (7) can improve the completeness of the extraction of the echo data corresponding to the reference target.

[0111] In some feasible implementations, step S2 above, determining the target amplitude-phase factor based on the target phase difference model and target amplitude-phase information, includes:

[0112] Step S21; Determine the target amplitude-phase factor according to the following formula:

[0113] (8)

[0114] in, Used to represent the target amplitude-phase factor; Used to indicate the transmitting antenna of the second target Second target receiving antenna Corresponding amplitude and phase information; Used to indicate the transmitting antenna of the first target and the first target receiving antenna Corresponding amplitude and phase information; Used to represent the imaginary unit.

[0115] In some feasible implementations, the above method further includes:

[0116] The target amplitude and phase factors are compensated according to the following formula. :

[0117] (9)

[0118] in, Used to indicate the transmitting antenna of the first target and the first target receiving antenna The corresponding complex value of the target detection point after correction; Used to indicate the transmitting antenna of the first target and the first target receiving antenna The complex value of the corresponding target detection point.

[0119] Step S3: Perform target amplitude and phase calibration operation based on the target amplitude and phase factor.

[0120] For example, the target amplitude and phase factor can be compensated accordingly. Perform target amplitude and phase calibration operations. These target amplitude and phase calibration operations may include: target amplitude and phase error calibration operations.

[0121] For example, Figures 3-6 This is a schematic diagram of the angular spectrum generated from multi-vehicle data collected using any vehicle as a target sample, as provided in this embodiment of the application. The parameters of the millimeter-wave radar to be calibrated are as follows: an 80G millimeter-wave radar with an array aperture of 0.2m.

[0122] Specifically, Figure 3 The angular-dimensional spectrum diagram corresponding to the absence of amplitude and phase calibration operation is derived from... Figure 3 It can be seen that, due to amplitude and phase errors, the angle dimension spectrum failed to form the sinc function envelope, resulting in the inability to obtain the angle information of the target vehicle.

[0123] Specifically, Figure 4 The diagram shows the angular spectrum corresponding to the amplitude-phase calibration operation performed using traditional methods under far-field conditions (i.e., a reference target distance of 20.5m). Figure 4 It can be seen that the angular dimension spectrum can form a relatively ideal sinc envelope, and a peak pointing to a certain angle appears.

[0124] Specifically, Figure 5 The diagram shows the angular spectrum corresponding to the amplitude-phase calibration operation performed using traditional methods under near-field conditions (i.e., a reference target distance of 3.5m).Figure 5 It can be seen that although a peak pointing to a certain angle appears in the angle dimension spectrum, the sinc envelope is severely distorted, leading to errors in the angle estimation results.

[0125] Specifically, Figure 6 The diagram shows the angular spectrum corresponding to the amplitude-phase calibration operation performed based on the method provided in this application under near-field conditions (i.e., a reference target distance of 3.5m). Figure 6 It can be seen that the above-mentioned angular dimensional spectrum can form a relatively ideal sinc envelope, with the peak clearly pointing to a specific angle, and its effect is similar to... Figure 4 The results under far-field conditions showed no significant difference.

[0126] Based on this, the millimeter-wave radar antenna array amplitude and phase calibration method provided in this application is applicable to near-field environments. The method includes: constructing a target phase difference model based on the target near-field calibration environment; determining the target amplitude and phase factor based on the target phase difference model and target amplitude and phase information; and performing target amplitude and phase calibration operations based on the target amplitude and phase factor. This method, by overcoming the limitations of far-field conditions, can reduce the cost and space required for anechoic chambers in millimeter-wave radar antenna array amplitude and phase calibration scenarios. By improving applicability to near-field environments, i.e., confined space scenarios, it can reduce testing distance, calibration time, and calibration efficiency, facilitating the integration of automated production lines for millimeter-wave radar antenna array amplitude and phase calibration, thereby improving production efficiency. The amplitude and phase calibration accuracy of the above method for millimeter-wave radar antenna arrays is equivalent to that under far-field conditions, which is beneficial for improving the amplitude and phase calibration accuracy of millimeter-wave radar antenna arrays in near-field environments.

[0127] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0128] The above is an introduction to the method embodiments. The following describes the solution described in this application through device embodiments.

[0129] A second aspect of this application provides a millimeter-wave radar antenna array amplitude and phase calibration device, applicable to the method described above. Figure 7 This is a structural schematic diagram of a millimeter-wave radar antenna array amplitude and phase calibration device 200 provided in an embodiment of this application. Figure 7The millimeter-wave radar antenna array amplitude and phase calibration device 200 shown includes: a construction unit 210, a determination unit 220, and an execution unit 230.

[0130] The building unit is used to construct a target phase difference model based on the target near-field calibration environment;

[0131] The determining unit is used to determine the target amplitude and phase factor based on the target phase difference model and target amplitude and phase information;

[0132] The execution unit is used to perform target amplitude and phase calibration operations based on the target amplitude and phase factor.

[0133] Figure 8 This is a schematic diagram of the structure of an electronic device 300 provided in an embodiment of this application. Figure 8 As shown, the electronic device 300 includes a central processing unit (CPU) 301, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 302 or a program loaded from a storage section 308 into a random access memory (RAM) 303. The RAM 303 also stores various programs and data required for the operation of the terminal device or server. The CPU 301, ROM 302, and RAM 303 are interconnected via a bus 304. An input / output (I / O) interface 305 is also connected to the bus 304.

[0134] The following components are connected to I / O interface 305: an input section 306 including a keyboard, mouse, etc.; an output section 307 including a cathode ray tube (CRT), liquid crystal display (LCD), etc., and speakers, etc.; a storage section 308 including a hard disk, etc.; and a communication section 309 including a network interface card such as a LAN card, modem, etc. The communication section 309 performs communication processing via a network such as the Internet. A drive 310 is also connected to I / O interface 305 as needed. A removable medium 311, such as a disk, optical disk, magneto-optical disk, semiconductor memory, etc., is installed on drive 310 as needed so that computer programs read from it can be installed into storage section 308 as needed.

[0135] Specifically, according to embodiments of this application, the above method flow steps can be implemented as a computer software program. For example, embodiments of this application include a computer program product comprising a computer program carried on a machine-readable medium, the computer program containing program code for performing the methods shown in the flowchart. In such embodiments, the computer program can be downloaded and installed from a network via communication section 309, and / or installed from removable medium 311. When the computer program is executed by central processing unit (CPU) 301, it performs the functions defined in the system of this application.

[0136] It should be noted that the computer-readable medium described in this application can be a computer-readable signal medium or a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example,—but not limited to—an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of a computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage device, magnetic storage device, or any suitable combination thereof. In this application, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system, apparatus, or device. In this application, a computer-readable signal medium can include a data signal propagated in baseband or as part of a carrier wave, carrying computer-readable program code. Such propagated data signals can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. Computer-readable signal media can also be any computer-readable medium other than computer-readable storage media, which can send, propagate, or transmit a program for use by or in connection with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium can be transmitted using any suitable medium, including but not limited to: wireless, wire, optical fiber, RF, etc., or any suitable combination thereof.

[0137] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0138] The units or modules described in the embodiments of this application can be implemented in software or hardware. The described units or modules can also be located in a processor. The names of these units or modules do not, in certain circumstances, constitute a limitation on the unit or module itself.

[0139] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the foregoing application concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions claimed in this application.

Claims

1. A method for amplitude and phase calibration of a millimeter-wave radar antenna array, characterized in that, Suitable for near-field environments, including: Based on the target near-field calibration environment, a target phase difference model is constructed, including: Based on the target near-field calibration environment, the physical distance to the target is calculated, including: determining the first physical distance according to the following formula: The second physical distance is determined using the following formula: in, Used to indicate the first physical distance; Used to indicate the transmitting antenna of the first target First reference coordinate axis The coordinate components of the direction; Used to indicate the transmitting antenna of the first target On the third reference coordinate axis The coordinate components of the direction; Used to indicate the second physical distance; Used to indicate the first target receiving antenna First reference coordinate axis The coordinate components of the direction; Used to indicate the first target receiving antenna On the third reference coordinate axis The coordinate components of the direction; Used to indicate the distance to the first reference target; Used to indicate the distance to the second reference target; Used to indicate the distance to the third benchmark target; Based on the physical distance to the target, construct the target phase difference model; Based on the target phase difference model and target amplitude and phase information, the target amplitude and phase factor is determined; the target amplitude and phase factor is determined according to the following formula: in, Used to represent the target amplitude-phase factor; Used to indicate the transmitting antenna of the second target Second target receiving antenna Corresponding amplitude and phase information; Used to indicate the transmitting antenna of the first target and the first target receiving antenna Corresponding amplitude and phase information; Used to represent the imaginary unit; Perform a target amplitude and phase calibration operation based on the target amplitude and phase factor.

2. The method according to claim 1, characterized in that, The step of constructing the target phase difference model based on the target physical distance includes: Determine the target phase difference based on the first physical distance and the second physical distance; Based on the target phase difference, construct the target phase difference model.

3. The method according to claim 1, characterized in that, Also includes: The target phase difference is determined according to the following formula: in, Used to represent the target phase difference; Used to indicate the transmitting antenna of the second target The corresponding first physical distance; Used to indicate the second target receiving antenna The corresponding second physical distance; Used to indicate the operating wavelength of the millimeter-wave radar to be calibrated.

4. The method according to claim 2, characterized in that, Also includes: The target amplitude-phase factor is compensated according to the following formula: in, Used to indicate the first target transmitting antenna and the first target receiving antenna The corresponding complex value of the target detection point after correction; Used to indicate the first target transmitting antenna and the first target receiving antenna The complex value of the corresponding target detection point.

5. The method according to any one of claims 1 to 4, characterized in that, Also includes: The target amplitude and phase information is extracted and generated based on the target distance index and / or the target Doppler index.

6. The method according to claim 5, characterized in that, Also includes: The target distance index is determined according to the following formula: in, Used to represent the target distance index; Used to indicate the target number of sampling points; Used to represent the target frequency modulation slope; Used to represent the speed of light; Used to represent the target sampling rate.

7. A millimeter-wave radar antenna array amplitude and phase calibration device, applicable to the method as described in claim 1, characterized in that, include: The building unit is used to construct a target phase difference model based on the target near-field calibration environment; The determining unit is used to determine the target amplitude-phase factor based on the target phase difference model and the target amplitude-phase information; An execution unit is used to perform a target amplitude and phase calibration operation based on the target amplitude and phase factor.

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