4D millimeter wave radar antenna array and 4D millimeter wave radar

Abstract

The utility model discloses a 4D millimeter-wave radar antenna array and a 4D millimeter-wave radar, which are applied to the technical field of millimeter-wave radars, a transmitting antenna array comprises a plurality of transmitting array elements, and a receiving antenna array comprises a plurality of receiving array elements; the transmitting antenna array comprises a horizontal transmitting antenna sub-array distributed in the horizontal direction and a vertical transmitting antenna sub-array distributed in the vertical direction, and the receiving antenna array comprises a horizontal receiving antenna sub-array distributed in the horizontal direction and a vertical receiving antenna sub-array distributed in the vertical direction. An antenna aperture with a large size is formed through the MIMO technology, so that the 4D millimeter wave radar antenna array has high angular resolution in both the horizontal direction and the vertical direction.

Description

Technical Field

[0001] The utility model relates to the technical field of millimeter wave radars, in particular to a 4D millimeter wave radar antenna array and a 4D millimeter wave radar. Background Art

[0002] With the development of economy and the progress of science and technology, cars are becoming more and more popular and have become an indispensable means of transportation in society. Although the popularity of cars has brought great convenience to people's production and life, it has also led to more frequent traffic accidents, which inevitably brought huge economic losses and casualties. Against this background, major automobile manufacturers around the world have invested in the research and development boom of vehicle-mounted assisted driving and autonomous driving. As an important member of the environmental perception unit of assisted driving and autonomous driving vehicles, millimeter wave radar plays a very important role, especially some functions related to safety, such as AEB (Autonomous Emergency Braking) automatic emergency braking system, BSD (Blind Spot Detection) blind spot detection system and ELK (Emergency lane-keeping system) emergency lane keeping system.

[0003] The current mainstream millimeter-wave radars still have limitations such as being unable to measure height, having low horizontal angular resolution, and being unable to detect stationary objects. Therefore, how to provide a 4D millimeter-wave radar antenna array with high angular resolution in both horizontal and vertical directions is an issue that technical personnel in this field urgently need to solve. Utility Model Content

[0004] The purpose of the utility model is to provide a 4D millimeter-wave radar antenna array having high angular resolution in both horizontal and vertical directions; another purpose of the utility model is to provide a 4D millimeter-wave radar having high angular resolution in both horizontal and vertical directions.

[0005] In order to solve the above technical problems, the utility model provides a 4D millimeter wave radar antenna array, including a transmitting antenna array and a receiving antenna array, wherein the transmitting antenna array includes a plurality of transmitting array elements, and the receiving antenna array includes a plurality of receiving array elements;

[0006] The transmitting antenna array includes a horizontal transmitting antenna subarray distributed in the horizontal direction and a vertical transmitting antenna subarray distributed in the vertical direction. The receiving antenna array includes a horizontal receiving antenna subarray distributed in the horizontal direction and a vertical receiving antenna subarray distributed in the vertical direction. Virtual array elements are formed by MIMO technology. The virtual array elements form a horizontal linear array distributed in the horizontal direction and a vertical linear array distributed in the vertical direction.

[0007] Optionally, the transmitting antenna array is provided with one horizontal transmitting antenna subarray and one vertical transmitting antenna subarray, and the receiving antenna array is provided with one horizontal receiving antenna subarray and one vertical receiving antenna subarray.

[0008] Optionally, the transmitting antenna array is L-shaped or T-shaped, and the receiving antenna array is L-shaped or T-shaped.

[0009] Optionally, the horizontal transmitting antenna subarray and the vertical transmitting antenna subarray have common transmitting array elements, and the horizontal receiving antenna subarray and the vertical receiving antenna subarray have common receiving array elements.

[0010] Optionally, the transmitting antenna array includes 12 transmitting array elements, the transmitting array elements include 1 transmitting array element located in the first row and 11 transmitting array elements located in the second row, and the transmitting array element located in the first row and the 7th transmitting array element located in the second row are aligned in columns.

[0011] Optionally, the transmitting array element located in the first row is spaced 4.5 wavelengths from the seventh transmitting array element located in the second row; among the transmitting array elements located in the second row, along the preset direction, the first transmitting array element is spaced 0.5 wavelengths from the second transmitting array element to the third transmitting array element, 1 wavelength from the third transmitting array element to the fourth transmitting array element, 1.5 wavelengths from the fourth to the eighth transmitting array elements are equally spaced 3.5 wavelengths apart, the eighth transmitting array element is spaced 2 wavelengths from the ninth transmitting array element, the ninth transmitting array element is spaced 2 wavelengths from the tenth transmitting array element, and the tenth transmitting array element is spaced 0.5 wavelength apart from the eleventh transmitting array element.

[0012] Optionally, the receiving antenna array includes 16 receiving array elements, the receiving array elements include 8 receiving array elements distributed in the horizontal direction and 8 receiving array elements distributed in the vertical direction, and the 8th receiving array element arranged in the horizontal direction is aligned in a column with the 8th receiving array element arranged in the vertical direction.

[0013] Optionally, adjacent receiving array elements distributed in the vertical direction and the 8th receiving array element arranged in the horizontal direction and the 8th receiving array element arranged in the vertical direction are equally spaced by 3 wavelengths;

[0014] Among the receiving array elements arranged in the horizontal direction, the first receiving array element and the second receiving array element along the preset direction are spaced 4.5 wavelengths apart, the second receiving array element and the third receiving array element are spaced 5.5 wavelengths apart, the third receiving array element and the fourth receiving array element are spaced 1.5 wavelengths apart, the fourth receiving array element and the fifth receiving array element are spaced 6.5 wavelengths apart, the fifth receiving array element and the sixth receiving array element are spaced 1.5 wavelengths apart, the sixth receiving array element and the seventh receiving array element are spaced 1.5 wavelengths apart, and the seventh receiving array element to the eighth receiving array element are spaced 11 wavelengths apart.

[0015] Optionally, the transmitting array element is a microstrip antenna or a waveguide antenna, and the receiving array element is a microstrip antenna or a waveguide antenna.

[0016] Optionally, the starting operating frequency of the transmitting array element is 76 GHz, the maximum bandwidth is 5 GHz, and the usable frequency range is 76 GHz-81 GHz; the starting operating frequency of the receiving array element is 76 GHz, the maximum bandwidth is 5 GHz, and the usable frequency range is 76 GHz-81 GHz.

[0017] Optionally, the operating modes of the transmitting array element and the receiving array element are both time division multiplexing, frequency division multiplexing, Doppler division multiplexing or code division multiplexing.

[0018] The utility model also provides a 4D millimeter wave radar, comprising the 4D millimeter wave radar antenna array as described in any one of the above items.

[0019] The utility model provides a 4D millimeter wave radar antenna array, including a transmitting antenna array and a receiving antenna array, the transmitting antenna array includes a plurality of transmitting array elements, and the receiving antenna array includes a plurality of receiving array elements; the transmitting antenna array includes a horizontal transmitting antenna subarray distributed in a horizontal direction and a vertical transmitting antenna subarray distributed in a vertical direction, the receiving antenna array includes a horizontal receiving antenna subarray distributed in a horizontal direction and a vertical receiving antenna subarray distributed in a vertical direction, virtual array elements are formed by MIMO technology, and the virtual array elements form a horizontal linear array distributed in the horizontal direction and a vertical linear array distributed in the vertical direction.

[0020] Based on the virtual aperture technology in the multiple-transmit multiple-receive mode, virtual array elements are formed. The transmitting antenna array and the receiving antenna array are set to extend in both the horizontal and vertical directions. A horizontal linear array distributed in the horizontal direction and a vertical linear array distributed in the vertical direction can be formed in the virtual array elements, thereby ensuring that a linear array with more virtual array elements is formed in both the horizontal and vertical directions, so that the 4D millimeter-wave radar antenna array has a higher angular resolution in both the horizontal and vertical directions.

[0021] The utility model also provides a 4D millimeter wave radar, which also has the above-mentioned beneficial effects and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the utility model or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic diagram of the structure of a 4D millimeter wave radar antenna array provided by an embodiment of the utility model;

[0024] Figure 2 A schematic diagram of a virtual array element formed when the transmitting array element of the embodiment of the present utility model transmits in time-sharing manner;

[0025] Figure 3 It is a schematic diagram of a virtual array element formed when all the transmitting array elements of the embodiment of the utility model transmit in time-sharing manner.

[0026] In the figure: 1. transmitting antenna array, 11. horizontal transmitting antenna subarray, 12. vertical transmitting antenna subarray, 2. receiving antenna array, 21. horizontal receiving antenna subarray, 22. vertical receiving antenna subarray, 31. horizontal linear array, 32. vertical linear array, 33. subarray. DETAILED DESCRIPTION

[0027] The core of the utility model is to provide a 4D millimeter wave radar antenna array. In the prior art, the current mainstream millimeter wave radar still has limitations such as being unable to measure height, having low horizontal angle resolution, and being unable to detect stationary objects.

[0028] The utility model provides a 4D millimeter-wave radar antenna array, including a transmitting antenna array and a receiving antenna array, the transmitting antenna array includes a plurality of transmitting array elements, and the receiving antenna array includes a plurality of receiving array elements; the transmitting antenna array includes a horizontal transmitting antenna subarray distributed in the horizontal direction and a vertical transmitting antenna subarray distributed in the vertical direction, the receiving antenna array includes a horizontal receiving antenna subarray distributed in the horizontal direction and a vertical receiving antenna subarray distributed in the vertical direction, virtual array elements are formed through MIMO technology, and the virtual array elements form a horizontal linear array distributed in the horizontal direction and a vertical linear array distributed in the vertical direction.

[0029] Based on the virtual aperture technology in the multiple-transmit multiple-receive mode, virtual array elements are formed. The transmitting antenna array and the receiving antenna array are set to extend in both the horizontal and vertical directions. A horizontal linear array distributed in the horizontal direction and a vertical linear array distributed in the vertical direction can be formed in the virtual array elements, thereby ensuring that a linear array with more virtual array elements is formed in both the horizontal and vertical directions, so that the 4D millimeter-wave radar antenna array has a higher angular resolution in both the horizontal and vertical directions.

[0030] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.

[0031] Embodiment 1

[0032] Please refer to Figure 1 , Figure 1 A schematic diagram of the structure of a 4D millimeter wave radar antenna array provided in an embodiment of the utility model.

[0033] See also Figure 1 In an embodiment of the utility model, a 4D millimeter-wave radar antenna array includes a transmitting antenna array 1 and a receiving antenna array 2, wherein the transmitting antenna array 1 includes a plurality of transmitting array elements, and the receiving antenna array 2 includes a plurality of receiving array elements; the transmitting antenna array 1 includes a horizontal transmitting antenna subarray 11 distributed in a horizontal direction and a vertical transmitting antenna subarray 12 distributed in a vertical direction, and the receiving antenna array 2 includes a horizontal receiving antenna subarray 21 distributed in a horizontal direction and a vertical receiving antenna subarray 22 distributed in a vertical direction, and virtual array elements are formed by MIMO technology, and the virtual array elements form a horizontal linear array 31 distributed in a horizontal direction, and a vertical linear array 32 distributed in a vertical direction.

[0034] In this embodiment, the antenna array includes a transmitting antenna array 1 and a receiving antenna array 2, and the transmitting antenna array 1 and the receiving antenna array 2 can be set in the same board. The units constituting the above-mentioned transmitting antenna array 1 are transmitting array elements, and the units constituting the receiving antenna array 2 are receiving array elements. In this embodiment, the transmitting array element will emit millimeter waves to the target object, and the receiving array element will receive the echo reflected by the target object. In this embodiment, the transmitting antenna array 1 and the receiving antenna array 2 will send and receive signals based on the virtual aperture technology in the multiple input multiple out (MIMO) mode, that is, virtual array elements are formed by MIMO technology. Obviously, in this embodiment, the arrangement of the virtual array elements is related to the arrangement of the transmitting array elements and the arrangement of the receiving array elements.

[0035] In this embodiment, the transmitting antenna array 1 includes a horizontal transmitting antenna subarray 11 distributed in the horizontal direction and a vertical transmitting antenna subarray 12 distributed in the vertical direction. The two transmitting antenna subarrays enable the transmitting antenna array 1 to form an array structure extending in both the horizontal and vertical directions. Correspondingly, in this embodiment, the receiving antenna array 2 includes a horizontal receiving antenna subarray 21 distributed in the horizontal direction and a vertical receiving antenna subarray 22 distributed in the vertical direction. The two receiving antenna subarrays enable the receiving antenna array 2 to also form an array structure extending in both the horizontal and vertical directions. Combined with the virtual aperture technology in the multiple transmission and multiple reception mode, it is possible to form a horizontal linear array 31 distributed in the horizontal direction and a vertical linear array 32 distributed in the vertical direction so that the virtual array elements are formed. The horizontal linear array 31 can enable the millimeter wave radar antenna array to have a high angular resolution in the horizontal direction, and the vertical linear array 32 can enable the millimeter wave radar antenna array to have a high angular resolution in the vertical direction, thereby forming a 4D millimeter wave radar antenna array.

[0036] Specifically, in this embodiment, any of the receiving array elements receives the echo formed by the millimeter waves emitted by all the transmitting array elements and reflected by the target object, so that the virtual array element forms a subarray 33 located outside the horizontal linear array 31 and the vertical linear array 32. That is, in this embodiment, the echo generated by the millimeter waves emitted by a transmitting array element will be received by all the receiving array elements, thereby forming a corresponding virtual array element. In this process, the echo formed by the millimeter waves emitted by each transmitting array element in the horizontal transmitting antenna subarray 11 and the virtual array element formed by each receiving array element in the horizontal receiving antenna subarray 21 will form the above-mentioned horizontal linear array 31, and the echo formed by the millimeter waves emitted by each transmitting array element in the vertical transmitting antenna subarray 12 and the virtual array element formed by each receiving array element in the vertical receiving antenna subarray 22 will form the above-mentioned vertical linear array 32. Obviously, in the virtual array element distribution diagram, the virtual array element distribution density in the area where the above-mentioned horizontal linear array 31 and the vertical linear array 32 are located will be significantly higher than the virtual array element distribution density at other positions.

[0037] In this embodiment, the virtual array element distribution diagram forms a sub-array 33 except for the above-mentioned horizontal linear array 31 and vertical linear array 32. The sub-array 33 includes virtual array elements formed by millimeter waves emitted by each transmitting array element in the horizontal transmitting antenna sub-array 11 and received by each receiving array element in the vertical receiving antenna sub-array 22, and virtual array elements formed by millimeter waves emitted by each transmitting array element in the vertical transmitting antenna sub-array 12 and received by each receiving array element in the horizontal receiving antenna sub-array 21. In layman's terms, horizontal transmission and horizontal reception in the antenna array will form a horizontal linear array 31, and vertical transmission and vertical reception will form a vertical linear array 32. The array elements formed in addition will form the above-mentioned sub-array 33, which includes virtual array elements formed by horizontal transmission and vertical reception, and vertical transmission and horizontal reception. In this embodiment, the azimuth and elevation angles can be estimated by using the two independent linear arrays formed in azimuth and elevation, namely, the horizontal linear array 31 and the vertical linear array 32, and then by pairing with the sub-array 33 outside the above two linear arrays, the two-dimensional angle information of the target can be estimated. The specific calculation process of matching through the sub-array 33 and the specific calculation process of estimating the azimuth angle and the elevation angle through the linear array can be referred to the prior art, and will not be described in detail here.

[0038] Typically, in this embodiment, the transmitting antenna array 1 is provided with only one horizontal transmitting antenna subarray 11 and one vertical transmitting antenna subarray 12, and the receiving antenna array 2 is provided with only one horizontal receiving antenna subarray 21 and one vertical receiving antenna subarray 22. The transmitting antenna array 1 and the receiving antenna array 2 of this structure can effectively simplify the structure of the transmitting antenna array 1 and the receiving antenna array 2 while ensuring the formation of a horizontal linear array 31 and a vertical linear array 32 with sufficient angular resolution. Of course, in this embodiment, the number of each antenna subarray is not specifically limited, and it can be two, three, or more, etc., depending on the specific situation.

[0039] On this basis, in order to ensure that the 4D millimeter wave radar antenna array has sufficient angular resolution in pitch, the transmitting antenna array 1 can be set in an L-shape or a T-shape, and the receiving antenna array 2 can be set in an L-shape or a T-shape. Of course, in this embodiment, the transmitting antenna array 1 and the receiving antenna array 2 can also be in other shapes, such as a cross shape, etc., which are not specifically limited here.

[0040] In this embodiment, in order to further increase the number of virtual array elements, the horizontal transmitting antenna subarray 11 and the vertical transmitting antenna subarray 12 may have a common transmitting array element, and the horizontal receiving antenna subarray 21 and the vertical receiving antenna subarray 22 may have a common receiving array element. The above-mentioned common transmitting array element can be used as the transmitting array element in the horizontal transmitting antenna subarray 11, and can also be used as the transmitting array element in the vertical transmitting antenna subarray 12, which is a transmitting array element shared by the two; correspondingly, the above-mentioned common receiving array element can be used as the receiving array element in the horizontal receiving antenna subarray 21, and can also be used as the receiving array element in the vertical receiving antenna subarray 22, which is a receiving array element shared by the two. The common array element corresponds to 2 points on the virtual aperture technology display end, which can increase the number of point clouds of virtual array elements without increasing the volume.

[0041] It should be emphasized that in this embodiment, the transmitting antenna array 1 and the receiving antenna array 2 are positionally independent antenna arrays, that is, the relative position relationship between the transmitting antenna array 1 and the receiving antenna array 2 can be set arbitrarily and can be selected according to the actual installation situation, and no specific limitation is made here.

[0042] A 4D millimeter-wave radar antenna array provided in an embodiment of the utility model forms virtual array elements based on the virtual aperture technology in the multiple-transmit and multiple-receive mode, and both the transmitting antenna array 1 and the receiving antenna array 2 are arranged as arrays extending in both the horizontal and vertical directions. A horizontal linear array 31 distributed in the horizontal direction and a vertical linear array 32 distributed in the vertical direction can be formed in the virtual array elements, thereby ensuring that a linear array with more virtual array elements is formed in both the horizontal and vertical directions, so that the 4D millimeter-wave radar antenna array has a higher angular resolution in both the horizontal and vertical directions.

[0043] The specific contents of a 4D millimeter wave radar antenna array provided by the utility model will be described in detail in the following utility model embodiments.

[0044] Embodiment 2

[0045] Please refer to Figure 2 as well as Figure 3 , Figure 2 A schematic diagram of a virtual array element formed when the transmitting array element of the embodiment of the present utility model transmits in time-sharing manner; Figure 3 It is a schematic diagram of a virtual array element formed when all the transmitting array elements of the embodiment of the utility model transmit in time-sharing manner.

[0046] The direction represented by the row below is the horizontal direction, and the direction represented by the column is the vertical direction. In an embodiment of the utility model, the transmitting antenna array 1 includes 12 transmitting array elements TX1-TX12, and the transmitting array elements include 1 transmitting array element located in the first row and 11 transmitting array elements located in the second row, and the transmitting array element located in the first row is aligned in columns with the 7th transmitting array element located in the second row. Correspondingly, in this embodiment, the receiving antenna array 2 includes 16 receiving array elements RX1-RX16, and the receiving array elements include 8 receiving array elements distributed in the horizontal direction and 8 receiving array elements distributed in the vertical direction, and the 8th receiving array element arranged in the horizontal direction is aligned in columns with the 8th receiving array element arranged in the vertical direction.

[0047] For the transmitting antenna array 1, its transmitting array elements TX1 and TX7 are arranged in columns, that is, arranged in the vertical direction; and the transmitting array elements TX2-TX11 are arranged in rows, that is, arranged in the horizontal direction, wherein the transmitting array element TX7 is a shared transmitting array element. The above-mentioned rows and columns are perpendicular to each other, forming an inverted "T"-shaped transmitting antenna array 1. The receiving array elements are divided into two groups, the receiving array elements RX1-RX8 are arranged in rows, and the receiving array elements RX8-RX16 are arranged in columns. The row arrangement group and the column arrangement group are perpendicular to each other, forming an inverted "L" shape, wherein the receiving array element RX8 is shared by the rows and columns. At this time, the virtual array elements formed by the transmitting antenna array 1 and the receiving antenna array 2 of the above structure can form an independent linear array in azimuth and elevation, estimate the azimuth and elevation angles, and then use the sub-array 33 outside the linear array for pairing to estimate the two-dimensional angle information of the target. The relative positions of all transmitting array elements and receiving array elements are independent of each other, that is, all transmitting array elements can achieve the angular resolution achieved by the 4D millimeter wave radar antenna array provided in this embodiment without restricting each other under the premise of maintaining the aforementioned relative position relationship. This embodiment specifically provides a 12-transmit 16-receive 4D millimeter wave radar MIMO antenna array, which uses a smaller array size to achieve extremely high azimuth and pitch angle resolution. It can be widely used in many assisted driving scenarios such as adaptive cruise control (ACC), automatic emergency braking (AEB), blind spot monitoring (BSD), lane change assist (LCA), reversing warning (RCTA) in the automotive field and higher-level autonomous driving scenarios, as well as regional monitoring and road detection in non-automotive fields.

[0048] In this embodiment, the transmitting array elements are preferably designed with non-equidistant spacing, the receiving array elements are designed with non-equidistant spacing between row arrangement groups, and the array elements are designed with equal spacing between columns. Sufficient space is left in the middle of the antenna array of this structure to arrange related RF transceiver chips.

[0049] Specifically for the transmitting antenna array 1, in this embodiment, the transmitting array element located in the first row is spaced 4.5 wavelengths from the 7th transmitting array element located in the second row; among the transmitting array elements located in the second row, along the preset direction, the first transmitting array element is spaced 0.5 wavelengths from the second transmitting array element to the third transmitting array element, 1 wavelength from the third transmitting array element to the fourth transmitting array element, 1.5 wavelengths from the fourth transmitting array element to the eighth transmitting array element are equally spaced 3.5 wavelengths from the adjacent ones, the eighth transmitting array element is spaced 2 wavelengths from the ninth transmitting array element, the ninth transmitting array element is spaced 2 wavelengths from the tenth transmitting array element, and the tenth transmitting array element is spaced 0.5 wavelength from the eleventh transmitting array element.

[0050] That is, in this embodiment, the transmitting array elements are arranged in two rows, and the columns of TX1 in the first row and TX7 in the second row are aligned. TX1 and TX7 are separated by 4.5 wavelengths. In the second row, TX2 and TX3 are separated by 0.5 wavelengths, TX3 and TX4 are separated by 1 wavelength, TX4 and TX5 are separated by 1.5 wavelengths, TX5 and TX6, TX6 and TX7, TX7 and TX8, TX8 and TX9 are separated by 3.5 wavelengths, TX9 and TX10, TX10 and TX11 are separated by 2 wavelengths, and TX11 and TX12 are separated by 0.5 wavelengths.

[0051] Correspondingly, for the receiving antenna array 2, in this embodiment, adjacent receiving array elements distributed in the vertical direction, and the 8th receiving array element arranged in the horizontal direction and the 8th receiving array element arranged in the vertical direction are evenly spaced by 3 wavelengths; among the receiving array elements arranged in the horizontal direction, the first receiving array element and the second receiving array element along the preset direction are spaced by 4.5 wavelengths, the second receiving array element and the third receiving array element are spaced by 5.5 wavelengths, the third receiving array element and the fourth receiving array element are spaced by 1.5 wavelengths, the fourth receiving array element and the fifth receiving array element are spaced by 6.5 wavelengths, the fifth receiving array element and the sixth receiving array element are spaced by 1.5 wavelengths, the sixth receiving array element and the seventh receiving array element are spaced by 1.5 wavelengths, and the seventh receiving array element to the eighth receiving array element are spaced by 11 wavelengths.

[0052] That is, in this embodiment, the receiving array elements are divided into two groups according to rows and columns. In the row arrangement group, RX1 and RX2 are spaced 4.5 wavelengths apart, RX2 and RX3 are spaced 5.5 wavelengths apart, RX3 and RX4 are spaced 1.5 wavelengths apart, RX4 and RX5 are spaced 6.5 wavelengths apart, RX5 and RX6, RX6 and RX7 are spaced 1.5 wavelengths apart, and RX7 and RX8 are spaced 11 wavelengths apart. In the column arrangement group, RX8-RX16 of the receiving array elements are spaced 3 wavelengths apart.

[0053] In this embodiment, the transmitting array element may be a microstrip antenna or a waveguide antenna, and the receiving array element may be a microstrip antenna or a waveguide antenna. The starting operating frequency of the transmitting array element is 76 GHz, the maximum bandwidth is 5 GHz, and the usable frequency range is 76 GHz-81 GHz; the starting operating frequency of the receiving array element is 76 GHz, the maximum bandwidth is 5 GHz, and the usable frequency range is 76 GHz-81 GHz. The working modes of the transmitting array element and the receiving array element are all time division multiplexing (TDMA), frequency division multiplexing (FDMA), Doppler division multiplexing (DDMA) or code division multiplexing (CDMA). Of course, the antenna array designed in this embodiment can be applicable to the transmitting method that can achieve the effect of multiple transmission and multiple reception to produce a virtual aperture by demodulating the signal at the receiving end. It should be noted that the wavelength in this implementation is any wavelength corresponding to the usable frequency range of the millimeter wave radar specified in the automotive millimeter wave radar industry standard. Among them, the usable frequency range is usually 76 GHz-81 GHz.

[0054] See also Figure 3 In this embodiment, the antenna array of the above structure specifically takes a MIMO radar with time division multiplexing (that is, each transmitting array element transmits in time division, and all receiving array elements receive at the same time) as an example, and the virtual array elements formed are as follows Figure 3 As shown, its generation principle is as follows Figure 2 When the transmitting array elements TX1 and TX2 transmit in time division and the 16 receiving array elements receive simultaneously, Figure 2 The virtual array element effect is shown in the figure. Two transmitting array elements will generate two groups of virtual array elements, and the relative positions of the virtual array elements in the group will not change. The position of TX2 is 4.5 wavelengths downward in the vertical direction and 10 wavelengths to the left in the horizontal direction relative to the position of TX1. The virtual array element group generated by TX2 is 4.5 wavelengths downward in the vertical direction and 10 wavelengths to the left in the horizontal direction relative to the virtual array element group generated by TX1. Similarly, when all transmitting antennas in the transmitting array element transmit in time, the effect of the entire virtual array element array is as shown in the figure below. Figure 3As shown. The positions of the 24 array elements marked with "×" in the bottom row overlap. The total number of virtual array elements that can be generated by 12 transmitting array elements and 16 receiving array elements is theoretically: 12×1=192, minus 24 overlapping virtual array elements, so there are 168 non-overlapping virtual array elements. These virtual array elements form independent linear arrays in azimuth and elevation to estimate the azimuth and elevation angles, and then estimate the two-dimensional angle information of the target by pairing sub-arrays 33. These non-overlapping virtual array elements, a total of 64 array elements in azimuth form a linear array with a virtual aperture of 53.5 wavelengths, and a total of 18 virtual array elements in elevation form a linear array with a virtual aperture of 28.5 wavelengths. Since the angle to be measured in the pitch direction is relatively small, the present application forms a substantially uniformly distributed vertical linear array 32 in the pitch direction for the purpose of facilitating setting and installation; since the angle to be measured in the horizontal azimuth direction is relatively large, the present application forms a non-uniform horizontal linear array 31 in the azimuth direction to avoid the occurrence of grating lobes that affect the measurement resolution. This embodiment uses the basic idea of ​​interpolation array transformation to transform the non-uniform linear array into a 107-element azimuth uniform linear array and a 57-element pitch uniform linear array with an interval of 0.5 wavelength.

[0055] The angular resolution is calculated by the formula: θr = λ / (N×d×cos(θ)); where N is the number of array elements and d is the interval between two adjacent array elements. The angular resolution is calculated with the target located directly in front of the radar (θ = 0 at this time), and the horizontal angular resolution of 53.5 wavelengths in the horizontal direction is θr = 1 / 53.5 (radians), which is converted into an angle of about 1.07°; similarly, the angular resolution of 28.5 wavelengths in the elevation direction is about 2.01°.

[0056] like Figure 3 As shown, in actual use at this stage, the horizontal field of view is about 120°, with a large range and the central area as the focus; in this embodiment, the virtual array element distribution is sparse in the middle and dense at the edges (this distribution takes into account the virtual aperture technology display end, signal coupling, etc.), and the 192 point clouds formed overlap only a small proportion; the intervals between the array elements are set to avoid the overlap of the point clouds of the integrated virtual aperture technology display end, reduce the amount of calculation, etc. The vertical field of view is usually only about twenty degrees at this stage, with a small range, so the array element antennas are evenly distributed to meet the use requirements.

[0057] In summary, the 4D millimeter-wave radar MIMO antenna array designed in this embodiment, if the wavelength is calculated at 77GHz, with the size of the transceiver array occupying 32 wavelengths in the horizontal direction, which is 12.47cm, and 24 wavelengths in the elevation direction, which is 9.35cm, can produce a virtual aperture effect of 53.5 wavelengths in the horizontal direction and 28.5 wavelengths in the elevation direction through MIMO. The theoretical angular resolutions in the horizontal and elevation directions can reach 1.07° and 2.01° respectively. Therefore, under the premise of a smaller antenna array space, extremely high angular resolutions are achieved in both the horizontal and elevation directions. This antenna array has a small size, high angular resolution, and good market application value.

[0058] Of course, in this embodiment, the above features and embodiments can be modified according to actual conditions, such as increasing or decreasing the number of transmitting and receiving array element antennas in azimuth or elevation, and changing the position of the array elements to adapt to specific conditions and materials, which all fall within the protection scope of the present utility model.

[0059] Embodiment 3

[0060] This embodiment also provides a 4D millimeter wave radar, which includes a 4D millimeter wave radar antenna array provided by any of the above utility model embodiments. In addition to the above antenna array, it can also include components such as a processor and a transceiver chip. The specific structure of the 4D millimeter wave radar antenna array has been described in detail in the above utility model embodiments, and will not be repeated here. The specific contents of the remaining components in the 4D millimeter wave radar can be referred to the prior art, and will not be repeated here.

[0061] Since the 4D millimeter-wave radar provided by the embodiment of the utility model includes the 4D millimeter-wave radar antenna array provided by any of the above-mentioned utility model embodiments, the 4D millimeter-wave radar of this embodiment has a high angular resolution in both azimuth and elevation directions.

[0062] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0063] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present utility model.

[0064] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0065] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0066] The above is a detailed introduction to a 4D millimeter-wave radar antenna array and a 4D millimeter-wave radar provided by the utility model. This article uses specific examples to illustrate the principles and implementation methods of the utility model. The description of the above embodiments is only used to help understand the method and core idea of ​​the utility model. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the utility model, the utility model can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the utility model.

Claims

1. A 4D millimeter wave radar antenna array, characterized in that: It comprises a transmitting antenna array (1) and a receiving antenna array (2), wherein the transmitting antenna array (1) comprises a plurality of transmitting array elements, and the receiving antenna array (2) comprises a plurality of receiving array elements; The transmitting antenna array (1) comprises a horizontal transmitting antenna subarray (11) distributed in the horizontal direction and a vertical transmitting antenna subarray (12) distributed in the vertical direction, and the receiving antenna array (2) comprises a horizontal receiving antenna subarray (21) distributed in the horizontal direction and a vertical receiving antenna subarray (22) distributed in the vertical direction. Virtual array elements are formed by MIMO technology, and the virtual array elements form a horizontal linear array (31) distributed in the horizontal direction and a vertical linear array (32) distributed in the vertical direction.

2. The 4D millimeter wave radar antenna array according to claim 1, characterized in that: The transmitting antenna array (1) is provided with a horizontal transmitting antenna subarray (11) and a vertical transmitting antenna subarray (12), and the receiving antenna array (2) is provided with a horizontal receiving antenna subarray (21) and a vertical receiving antenna subarray (22).

3. The 4D millimeter wave radar antenna array according to claim 2, characterized in that: The transmitting antenna array (1) is in an L-shape or a T-shape, and the receiving antenna array (2) is in an L-shape or a T-shape.

4. The 4D millimeter wave radar antenna array according to any one of claims 1 to 3, characterized in that: The horizontal transmitting antenna subarray (11) and the vertical transmitting antenna subarray (12) have a common transmitting array element, and the horizontal receiving antenna subarray (21) and the vertical receiving antenna subarray (22) have a common receiving array element.

5. The 4D millimeter wave radar antenna array according to claim 4, characterized in that: The transmitting antenna array (1) comprises 12 transmitting array elements, wherein the transmitting array elements comprise 1 transmitting array element located in a first row and 11 transmitting array elements located in a second row, and the transmitting array element located in the first row and the 7th transmitting array element located in the second row are aligned in columns.

6. The 4D millimeter wave radar antenna array according to claim 5, characterized in that: The transmitting array element located in the first row is spaced 4.5 wavelengths from the 7th transmitting array element located in the second row; among the transmitting array elements located in the second row, along the preset direction, the first transmitting array element is spaced 0.5 wavelengths from the second transmitting array element to the third transmitting array element, 1 wavelength from the third transmitting array element to the fourth transmitting array element, 3.5 wavelengths from the fourth to the eighth transmitting array elements are equally spaced from each other, 2 wavelengths from the eighth transmitting array element to the ninth transmitting array element, 2 wavelengths from the ninth transmitting array element to the tenth transmitting array element, and 0.5 wavelengths from the tenth transmitting array element to the eleventh transmitting array element.

7. The 4D millimeter wave radar antenna array according to claim 4, characterized in that: The receiving antenna array (2) comprises 16 receiving array elements, wherein the receiving array elements comprise 8 receiving array elements distributed in a horizontal direction and 8 receiving array elements distributed in a vertical direction, and the 8th receiving array element arranged in the horizontal direction is aligned in a column with the 8th receiving array element arranged in the vertical direction.

8. The 4D millimeter wave radar antenna array according to claim 7, characterized in that: Adjacent receiving array elements distributed in the vertical direction and the 8th receiving array element arranged in the horizontal direction and the 8th receiving array element arranged in the vertical direction are equally spaced by 3 wavelengths; Among the receiving array elements arranged in the horizontal direction, the first receiving array element and the second receiving array element along the preset direction are spaced 4.5 wavelengths apart, the second receiving array element and the third receiving array element are spaced 5.5 wavelengths apart, the third receiving array element and the fourth receiving array element are spaced 1.5 wavelengths apart, the fourth receiving array element and the fifth receiving array element are spaced 6.5 wavelengths apart, the fifth receiving array element and the sixth receiving array element are spaced 1.5 wavelengths apart, the sixth receiving array element and the seventh receiving array element are spaced 1.5 wavelengths apart, and the seventh receiving array element to the eighth receiving array element are spaced 11 wavelengths apart.

9. The 4D millimeter wave radar antenna array according to claim 1, characterized in that: The transmitting array element is a microstrip antenna or a waveguide antenna, and the receiving array element is a microstrip antenna or a waveguide antenna.

10. The 4D millimeter wave radar antenna array according to claim 1, characterized in that: The starting operating frequency of the transmitting array element is 76 GHz, the maximum bandwidth is 5 GHz, and the usable frequency range is 76 GHz-81 GHz; the starting operating frequency of the receiving array element is 76 GHz, the maximum bandwidth is 5 GHz, and the usable frequency range is 76 GHz-81 GHz.

11. The 4D millimeter wave radar antenna array according to claim 1, characterized in that: The working modes of the transmitting array element and the receiving array element are both time division multiplexing, frequency division multiplexing, Doppler division multiplexing or code division multiplexing.

12. A 4D millimeter wave radar, characterized in that: Comprising a 4D millimeter wave radar antenna array as claimed in any one of claims 1 to 11.

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