Millimeter wave radar array antenna and radar device

Abstract

The present invention discloses a millimeter wave radar array antenna and a radar device, comprising: a substrate; an antenna, which is arranged on the substrate; a barrier layer, which is arranged on the substrate and is located between two adjacent antennas, the barrier layer being grounded, wherein the barrier layer has at least two barrier structures on the side adjacent to the antenna, and a groove recessed toward the barrier layer is formed between adjacent barrier structures, and the groove is used to suppress the surface waves excited by the antenna. In the present invention, the antenna is arranged on the substrate, the barrier layer is arranged on the substrate and is located between two adjacent antennas, an equivalent capacitor is formed between the barrier structures, and an equivalent inductance is formed by the current path generated by the current from the barrier structure through the via hole. When resonance occurs in a preset frequency band, the surface of the groove recessed toward the barrier layer formed between adjacent barrier structures generates a high impedance characteristic, which is used to suppress the surface waves excited by the antenna.

Description

Technical Field

[0001] The present invention relates to the field of radar technology, and in particular to a millimeter wave radar array antenna and a radar device. Background Art

[0002] As people's awareness of safety gradually increases, vehicle-mounted millimeter-wave anti-collision radar has developed rapidly as a safety prevention system. Its advantages such as small structure, light weight, strong environmental adaptability, stability and reliability have been highlighted in the application of vehicle-mounted anti-collision radar. Vehicle-mounted anti-collision radar is mainly used to detect objects around the car, provide prompts and safety warnings for the surrounding targets, and ensure driving safety. Vehicle-mounted millimeter-wave radar senses the environment through millimeter waves, such as detecting the distance between the front and rear vehicles, lane markings, etc.

[0003] Due to the high frequency band and thin substrate, the millimeter wave radar array antenna will excite surface waves, causing fluctuations in its radiation pattern, and the radiation pattern will change with the change of substrate size. The excited surface waves will propagate to both sides along the interface and form radiation at the edge of the substrate.

[0004] Therefore, it is urgent to design a new millimeter-wave radar array antenna to solve the defects of the existing technology. Summary of the invention

[0005] The purpose of the present invention is to provide a millimeter wave radar array antenna and a radar device in an embodiment of the present invention, aiming to effectively solve the problem that the surface waves formed by the antenna in the prior art will propagate to both sides along the interface and form radiation at the edge of the substrate.

[0006] According to one aspect of the present invention, the present invention provides a millimeter wave radar array antenna, comprising: a substrate; an antenna, arranged on the substrate; a barrier layer, arranged on the substrate and located between two adjacent antennas, the barrier layer being grounded, wherein the side of the barrier layer adjacent to the antenna has at least two barrier structures, and grooves recessed into the barrier layer are formed between adjacent barrier structures to suppress surface waves excited by the antenna.

[0007] Furthermore, the millimeter wave radar array antenna also includes a ground plate, and the substrate is arranged on the ground plate.

[0008] Furthermore, the barrier structure is in the shape of a triangle, an arc or a trapezoid.

[0009] Furthermore, a plurality of via holes are arranged along the edge of the barrier layer, and the via holes penetrate the substrate to connect the barrier layer with the ground plate.

[0010] Further, when the barrier structure is a triangular structure, the triangular structure is an isosceles triangle or an equilateral triangle, wherein the length of the sides with equal lengths in the triangular structure is 1.1 mm to 3.3 mm.

[0011] Furthermore, the plurality of vias are arranged at equal intervals.

[0012] Furthermore, the material of the barrier layer is a metal material.

[0013] Furthermore, the via hole is one of a circle, a triangle or a quadrilateral.

[0014] Furthermore, the substrate is a non-conductive material, an equivalent capacitor is formed between the barrier structures, and the current path generated by the current from the barrier structure through the via hole forms an equivalent inductance. When resonance occurs in a preset frequency band, the surface of the grooves formed between the adjacent barrier structures and sunken toward the barrier layer generates a high impedance characteristic for suppressing the surface waves excited by the antenna.

[0015] Furthermore, the barrier structure is arranged along the length direction of the antenna, and the plurality of barrier structures are arranged at equal distances.

[0016] According to another aspect of the present invention, the present invention provides a radar device, comprising the millimeter wave radar array antenna described in any embodiment of the present invention.

[0017] The advantage of the present invention lies in that the antenna is arranged on the substrate, the barrier layer is arranged on the substrate and is located between two adjacent antennas, an equivalent capacitor is formed between the barrier structures, and the current path generated by the current passing through the via hole from the barrier structure forms an equivalent inductor, and when resonance occurs in a preset frequency band, the surface of the grooves formed between adjacent barrier structures and recessed toward the barrier layer generates a high impedance characteristic for suppressing the surface waves excited by the antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The technical solutions and other beneficial effects of the present invention will be made apparent by describing in detail the specific embodiments of the present invention in conjunction with the accompanying drawings.

[0019] Figure 1 A schematic diagram of the structure of a millimeter wave radar array antenna provided in Embodiment 1 of the present invention.

[0020] Figure 2 for Figure 1 Cross-section view at AA in the middle.

[0021] Figure 3 A reference schematic diagram of the refraction direction of the surface wave generated on the substrate.

[0022] Figure 4This is a performance test diagram of the millimeter wave radar array antenna.

[0023] Figure 5 A schematic diagram of the structure of a millimeter wave radar array antenna provided in Embodiment 2 of the present invention.

[0024] Figure 6 A schematic diagram of the structure of a radar device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0025] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] like Figure 1 , which is a schematic diagram of the structure of the millimeter wave radar array antenna provided in Embodiment 1 of the present invention. The millimeter wave radar array antenna comprises: a substrate 300, an antenna 200, a barrier layer 100 and a ground plate 400.

[0028] The antenna 200 is arranged on the substrate 300, the barrier layer 100 is arranged on the substrate 300 and is located between two adjacent antennas 200, the barrier layer 100 is grounded, wherein the side of the barrier layer 100 adjacent to the antenna 200 has at least two barrier structures 110, and grooves 112 recessed toward the barrier layer 100 are formed between adjacent barrier structures 110, and the grooves 112 are used to suppress (or block) surface waves excited by the antenna.

[0029] The various components in the millimeter wave radar array antenna will be further described below.

[0030] The barrier structure 110 is arranged along the length direction of the antenna 200. Optionally, a plurality of barrier structures 110 are arranged equidistantly on the edge side of the barrier layer 100. The edge is adjacent to the antenna 200 and is a non-linear edge.

[0031] When the non-linear edge of the barrier layer 100 is a serrated edge, the serrated edge may be a triangular edge, a trapezoidal edge, or a rectangular edge. In other words, the barrier structure 110 of the barrier layer 100 may be a triangular structure, a trapezoidal structure, or a rectangular structure. In this embodiment, when the barrier structure 110 is a triangular structure, the triangular structure may be an isosceles triangle or an equilateral triangle, wherein the length of the sides of the triangular structure with equal lengths may be 1.1 mm to 3.3 mm. In other embodiments, the barrier structure 110 may also be a trapezoidal structure, a rectangular structure, a curved structure, or the like.

[0032] During manufacture, the barrier layer 100 can be formed in one piece with the barrier structure 110, and one-piece forming can facilitate production and manufacturing. The jagged edge includes at least one triangular structure. Further, the number of triangular structures is greater than or equal to two. It should be noted that "at least one" herein, when used with a series of items, means that different combinations of one or more listed items can be used, and only one of each item in the list may be required. For example, "at least one of item A, item B, and item C" may include, but is not limited to, item A or item A and item B. This example may also include item A, item B, and item C, or item B and item C. In other examples, "at least one" may be, for example, but not limited to, two items A, one item B and ten items C, four items B and seven items C, or some other suitable combination.

[0033] Continue reading Figure 1 As shown, a plurality of vias 111 are arranged along the edge of the barrier layer 100 (including the edge of the barrier structure 110), and the vias 111 penetrate the substrate 300 to connect the barrier layer 100 with the ground plate 400. The vias are circular, triangular or quadrilateral. In this embodiment, the vias are circular. Further, the plurality of vias 111 can be arranged equidistantly.

[0034] See also Figure 2 As shown, the substrate 300 is disposed on the grounding plate 400. The substrate 300 is a non-conductive material, such as a composite material of ceramic fillers. The material of the barrier layer 100 is a metal material, such as copper, iron. Figure 1 and Figure 2 As shown, an equivalent capacitor is formed between the barrier structures, and an equivalent inductor is formed by the current path generated by the current flowing from the barrier structure through the via hole. When resonance occurs in a preset frequency band, the surface of the grooves that are recessed into the barrier layer formed between adjacent barrier structures generates a high impedance characteristic for suppressing the surface waves excited by the antenna.

[0035] Continue reading Figure 2As shown, the barrier layer 100 is disposed on a first surface of the substrate 300, and the ground plate 400 is disposed on a second surface ( Figure 2 The thickness relationship among the substrate 300, the barrier layer 100 and the ground plate 400 is only for illustration purposes).

[0036] Combination Figure 1 and Figure 3 As shown, Figure 3 The arrows in the figure illustrate the diffusion of the surface waves when they appear on the antenna 200. The surface waves will diffuse from the center line of the antenna 200 to both sides of the antenna 200. Since the barrier layer 100 has a non-linear edge, the surface waves will be reflected multiple times at the edge of the barrier layer 100, thereby increasing the loss of the surface waves, thereby reducing the influence of the surface waves on the effect of transmitting and receiving RF signals of the barrier layer 100. When the barrier structure corresponding to the non-linear edge is a triangular structure, the manufacturer can set the length of each side of the triangular structure according to actual needs. For example, the triangular structure is an isosceles triangle or an equilateral triangle, and the length of the equal sides in the triangular structure is 1.1 mm to 3.3 mm. For another example, combined with Figure 3 As shown, ΔABC is an isosceles triangle, wherein the vertical line segment AB is perpendicular to the side CD. The following factors need to be considered when setting the vertical line segment AB and the side CD: if the length of the vertical line segment AB or the side CD is too small, the processing difficulty will increase; if the length of the vertical line segment AB or the side CD is too large, the number of triangular structures will be reduced, thereby reducing the filtering effect of the surface wave. Furthermore, the non-linear edge is consistent with the extension direction of the antenna 200.

[0037] In the first embodiment of the present invention, the antenna 200 is arranged on the substrate 300, the barrier layer 100 is arranged on the substrate 300 and is located between two adjacent antennas 200, the substrate 300 is a non-conductive material, an equivalent capacitor is formed between the barrier structures, and the current path generated by the current from the barrier structure through the via hole forms an equivalent inductance. When resonance occurs in a preset frequency band, the surface of the groove formed between the adjacent barrier structures and sunken toward the barrier layer generates a high impedance characteristic for suppressing the surface wave excited by the antenna. .

[0038] See also Figure 4 As shown, Figure 4 is a performance test diagram of the antenna 200 with a jagged edge. Figure 4 The Y axis of the coordinate system is the gain of the antenna 200, and the X axis is the angle (Theta, in degrees). Compared with conventional antennas, the RF signal fluctuation of the antenna 200 provided in this embodiment is smaller. In other words, through the design of the above structure, the performance of the antenna 200 in transmitting and receiving RF signals at different angles is more stable, and the barrier layer 100 has a better effect in filtering surface waves.

[0039] like Figure 5 FIG. 2 is a schematic diagram of the structure of a millimeter wave radar array antenna provided in Embodiment 2 of the present invention. The millimeter wave radar array antenna comprises: a substrate 300 , an antenna 200 , a barrier layer 100 and a ground plate 400 .

[0040] The antenna 200 is disposed on the substrate 300, the barrier layer 100 is disposed on the substrate 300 and is located between two adjacent antennas 200, the barrier layer 100 is grounded, the barrier layer 100 has at least two barrier structures 110 on the side adjacent to the antenna 200, and a groove 112 is formed between adjacent barrier structures 110 and is recessed toward the barrier layer 100. The groove 112 is used to suppress the surface wave excited by the antenna.

[0041] The barrier structure 110 is arranged along the length direction of the antenna 200. Optionally, a plurality of the barrier structures 110 are arranged equidistantly on the edge side of the barrier layer 100. The edge is adjacent to the antenna 200 and is a non-linear edge.

[0042] When the non-linear edge of the barrier layer 100 is a trapezoidal edge, that is, the barrier structure 110 of the barrier layer 100 correspondingly presents a trapezoidal structure, such as Figure 5 As shown. During production, the barrier layer 100 and the barrier structure 110 can be formed at one time, and the one-time forming can facilitate production and manufacturing. The trapezoidal edge includes a plurality of trapezoidal structures. The plurality of trapezoidal structures are arranged at equal intervals on the trapezoidal edge, so that when the antenna 200 fails, the difficulty of troubleshooting can be reduced. In addition, the above equal-distance arrangement can also reduce the difficulty of processing. Of course, the spacing value of the trapezoidal structures when arranged at equal intervals can be zero. Further, Figure 5 The length of the lower side CD of the middle trapezoidal structure is 1 to 2 times the wavelength of the radio frequency signal received and transmitted by the antenna 200 in the air. The length of the height AB perpendicular to the lower side is 1 to 2 times the wavelength of the radio frequency signal received and transmitted by the antenna 200 in the air. Manufacturers can set the length of each side of the trapezoidal structure according to actual needs. Figure 5 If the length of the lower bottom side CD or the height AB is too small, it will increase the difficulty of processing; Figure 5 If the length of the lower bottom side CD or the height AB is too large, the number of trapezoidal structures on the barrier layer 100 will be reduced, thereby reducing the filtering effect of the surface wave.

[0043] Continue reading Figure 1 As shown, a plurality of via holes 111 are arranged along the edge of the barrier layer 100 (including the edge of the barrier structure 110), and the via holes 111 penetrate the substrate 300 to connect the barrier layer 100 with the grounding plate 400. The via holes are circular. Furthermore, the plurality of via holes 111 can be arranged at equal intervals.

[0044] like Figure 2 As shown, the substrate 300 is disposed on the grounding plate 400. The substrate 300 is a non-conductive material, such as a composite material of ceramic fillers. The material of the barrier layer 100 is a metal material, such as copper, iron. Figure 1 and Figure 2 As shown, the substrate 300 is a non-conductive material, an equivalent capacitor is formed between the barrier structures, and the current path generated by the current from the barrier structure through the via hole forms an equivalent inductance. When resonance occurs in a preset frequency band, the surface of the grooves formed between the adjacent barrier structures and sunken toward the barrier layer generates a high impedance characteristic for suppressing the surface waves excited by the antenna.

[0045] Continue reading Figure 2 As shown, the barrier layer 100 is disposed on a first surface of the substrate 300, and the ground plate 400 is disposed on a second surface ( Figure 2 The thickness relationship among the substrate 300, the barrier layer 100 and the ground plate 400 is only for illustration purposes).

[0046] In the second embodiment of the present invention, the antenna is arranged on the substrate, the barrier layer is arranged on the substrate and is located between two adjacent antennas, an equivalent capacitor is formed between the barrier structures, and the current path generated by the current passing through the via hole from the barrier structure forms an equivalent inductor, and when resonance occurs in a preset frequency band, the surface of the grooves formed between the adjacent barrier structures and recessed toward the barrier layer generates a high impedance characteristic for suppressing the surface waves excited by the antenna.

[0047] like Figure 6 As shown, the present invention further provides a radar device 1000, and the radar device 1000 includes the millimeter wave radar array antenna 800 described in any embodiment of the present invention.

[0048] In summary, although the present invention has been disclosed as above in terms of preferred embodiments, the above preferred embodiments are not intended to limit the present invention. A person skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined in the claims.

Claims

1. A millimeter wave radar array antenna, characterized in that: include: substrate; An antenna is disposed on the substrate; A barrier layer is disposed on the substrate and located between two adjacent antennas, the barrier layer is grounded, wherein the barrier layer has at least two barrier structures on a side adjacent to the antenna, and a groove recessed toward the barrier layer is formed between adjacent barrier structures, and the groove is used to suppress surface waves excited by the antenna; A grounding plate, wherein the substrate is arranged on the grounding plate; A plurality of via holes are arranged along the edge of the barrier layer, and the via holes penetrate the substrate and are used to connect the barrier layer with the ground plate.

2. The millimeter wave radar array antenna according to claim 1, characterized in that: The barrier structure is in the shape of a triangle, an arc or a trapezoid.

3. The millimeter wave radar array antenna according to claim 2, characterized in that: When the barrier structure is a triangular structure, the triangular structure is an isosceles triangle or an equilateral triangle, wherein the length of the sides with equal lengths in the triangular structure is 1.1 mm to 3.3 mm.

4. The millimeter wave radar array antenna according to claim 1, characterized in that: The plurality of vias are arranged at equal distances.

5. The millimeter wave radar array antenna according to claim 4, characterized in that: The via hole is in the shape of a circle, a triangle or a quadrilateral.

6. The millimeter wave radar array antenna according to claim 1, characterized in that: The material of the barrier layer is a metal material.

7. The millimeter wave radar array antenna according to claim 6, characterized in that: The substrate is a non-conductive material, an equivalent capacitor is formed between the barrier structures, and an equivalent inductor is formed by the current path generated by the current passing through the barrier structure through the via hole. When resonance occurs in a preset frequency band, the surface of the grooves formed between adjacent barrier structures and recessed toward the barrier layer generates a high impedance characteristic for suppressing the surface waves excited by the antenna.

8. The millimeter wave radar array antenna according to any one of claims 1 to 7, characterized in that: The blocking structure is arranged along the length direction of the antenna, and the plurality of blocking structures are arranged at equal intervals.

9. A radar device, characterized in that: include: The millimeter wave radar array antenna as described in any one of claims 1 to 8.

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