Radiation slot structure suitable for waveguide antenna, waveguide transmission line, waveguide antenna radar and automobile

Abstract

The utility model provides a radiation slot structure suitable for a waveguide antenna and a waveguide transmission line, and the structure comprises a waveguide antenna which is provided with a waveguide transmission cavity; one or more radiation slots are formed in the top of the waveguide antenna in a penetrating mode, magnetic conductor nail columns are arranged on the top face of the H face of the waveguide transmission cavity, the magnetic conductor nail columns are arranged on the two sides of the radiation slots in the signal transmission direction to form nail column sets, and the geometric centers of the nail column sets and the geometric centers of the radiation slots are arranged in an offset mode. According to the utility model, the design of the nail column groups is adopted, each nail column group corresponds to one radiation slot, and the centers of the nail column groups and the radiation slots are offset, so that small offset or no offset is kept between the radiation slots, thereby improving the signal transmission efficiency of the waveguide antenna, reducing the difficulty of antenna performance debugging, and improving the efficiency of design iteration.

Description

Technical Field

[0001] The utility model relates to the technical field of waveguides, and in particular to a radiation slot structure suitable for a waveguide antenna and a waveguide transmission line. Background Art

[0002] With the rapid development of wireless communication technology, microwaves and millimeter waves have gradually come into people's view and play an important role in the field of communications.

[0003] Currently, waveguide antennas are gaining increasing attention in automotive millimeter-wave radar applications due to their advantages such as low loss and high isolation. Waveguide antennas are equipped with one or more radiation slots for transmitting or receiving signals. To improve signal transmission efficiency, a radiation slot structure suitable for waveguide antennas is needed to solve this problem. Utility Model Content

[0004] In view of the defects in the prior art, the purpose of the present invention is to provide a radiation slot structure and a waveguide transmission line suitable for a waveguide antenna.

[0005] According to the utility model, a radiation slot structure suitable for a waveguide antenna is provided, comprising: a waveguide antenna having a waveguide transmission cavity;

[0006] One or more radiation slots are provided through the top of the waveguide antenna, and a magnetic conductor nail post is provided on the top surface of the H-surface of the waveguide transmission cavity. The magnetic conductor nail posts are arranged on both sides of the radiation slot along the signal transmission direction to form a nail post group, and the geometric center of the nail post group is offset from the geometric center of the radiation slot.

[0007] Preferably, the number of the nail column groups is equal to the number of the radiation slots and they are arranged in a one-to-one correspondence;

[0008] The geometric centers of two adjacent nail column groups are offset from each other, and the geometric centers of multiple nail column groups are staggered.

[0009] Preferably, the magnetic conductor nail pin is also arranged at the end of the last nail pin group along the signal transmission direction to form an end nail pin group;

[0010] The distance between the end nail column group and the center of the last top column group is 1 / 4 of the waveguide wavelength.

[0011] Preferably, the center spacing and offset of adjacent nail column groups are such that the offset of the corresponding radiation slot relative to the nail column group is close to or satisfies Taylor distribution or Chebyshev distribution.

[0012] Preferably, a shielding wall is further provided on the top surface of the H-surface of the waveguide transmission cavity, and the shielding wall is located outside the magnetic conductor nail column.

[0013] Preferably, it also includes a PCB main board;

[0014] The PCB main board includes a metallization layer and a dielectric material on the top surface, wherein the metallization layer completely or partially covers the dielectric material;

[0015] The metallization layer, the magnetic conductor nail post, the waveguide antenna and the shielding wall surround a waveguide transmission cavity, wherein the magnetic conductor nail post and the shielding wall constitute two E-face side surfaces and two end faces of the waveguide transmission cavity, the waveguide antenna constitutes the H-face top surface of the waveguide transmission cavity, and the metallization layer constitutes the H-face bottom surface of the waveguide transmission cavity.

[0016] Preferably, the radiation slot includes a lower radiation slot and an upper radiation slot, the lower radiation slot and the upper radiation slot are symmetrically arranged along the signal transmission direction, and the front and rear lengths are the same, and the width of the lower radiation slot is smaller than the width of the upper radiation slot.

[0017] Particularly preferably, a ridge is provided at the center of the top surface of the H-plane of the waveguide transmission cavity; the ridges are evenly arranged in the waveguide transmission cavity, and no ridge 13 is provided in the middle of the nail column group 111; in the area close to the first group of nail columns, the height of the ridge gradually decreases until it is 0.

[0018] A waveguide transmission line provided by the present invention includes the radiation slot structure applicable to the waveguide antenna.

[0019] A waveguide antenna radar provided by the present invention includes the waveguide transmission line.

[0020] According to the utility model, a car is provided, comprising the waveguide antenna radar.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention adopts a spike group design, where each spike group corresponds to a radiation slot. By offsetting the spike group from the center of the radiation slot, a small offset or no offset is maintained between the radiation slots, thereby improving the signal transmission efficiency of the waveguide antenna, reducing the difficulty of antenna performance debugging, and improving the efficiency of design iteration.

[0023] 2. The present invention adopts a plurality of nail column groups corresponding to the radiation slots one by one, and offsets the nail column groups in sequence as a whole, so that the radiation slots cut the current in opposite directions and phases, thereby realizing slot array radiation.

[0024] 3. The radiation slot in this utility model adopts a double-layer design. The lower slot is narrower and serves as the main debugging feature of the antenna S parameters; the upper slot is wider and serves as the main debugging feature of the antenna radiation directivity. Step-by-step debugging helps to speed up the efficiency of antenna design and debugging.

[0025] 4. The utility model adopts a single-layer waveguide antenna structure design, using the metallized layer on the top surface of the PCB as the bottom surface of the H-surface of the waveguide transmission cavity to achieve a single-layer waveguide antenna single-layer structure, reducing manufacturing difficulty and reducing parts costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Other features, objects and advantages of the present invention will become more apparent from the detailed description of the non-limiting embodiments with reference to the following drawings:

[0027] Figure 1 This is a three-dimensional diagram of the radiation slot of the single-layer structure waveguide in the utility model;

[0028] Figure 2 This is a schematic diagram of the matching between the waveguide radiation gap and the PCB mainboard in the utility model;

[0029] Figure 3 This is a bottom view of the waveguide radiation slot structure in the utility model;

[0030] Figure 4 This is a cross-sectional view of the radiation gap in the utility model;

[0031] Figure 5 Schematic diagram of S parameters in an embodiment of the present invention. S parameters (Scatter parameters) are scattering parameters. In the figure, S(1,1) represents the reflection coefficient of port 1 when port 2 is matched, that is, the input return loss.

[0032] Figure 6 : is the directional diagram in the embodiment of the present utility model, in which Azim is the azimuth angle and Elev is the elevation angle.

[0033] Description of reference numerals:

[0034] DETAILED DESCRIPTION

[0035] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art further understand the present invention, but are not intended to limit the present invention in any way. It should be noted that a person skilled in the art may make various variations and improvements without departing from the scope of the present invention. Such variations and improvements are all within the scope of protection of the present invention.

[0036] The utility model discloses a radiation slot structure suitable for a waveguide antenna, which mainly comprises a waveguide antenna 1 having a waveguide transmission cavity 30.

[0037] In a preferred embodiment, a PCB mainboard 2 is further included, wherein the waveguide antenna 1 is a single-layer waveguide structure, and the waveguide antenna 1 and the PCB mainboard 2 together form a waveguide transmission cavity 30.

[0038] One or more radiation slots 10 are provided on the top of the waveguide antenna 1 , and the radiation slots 10 run through the top layer of the waveguide antenna 1 . In a preferred embodiment, 4 to 10 radiation slots 10 are provided to form a radiation slot array.

[0039] Magnetic conductor studs 11 are disposed below the waveguide antenna 1. They are equidistantly spaced along the signal transmission direction. The spacing between the studs 11 meets the requirements of 76-81 GHz, typically 2.3-2.7 mm. The studs 11 are cylindrical or rectangular, with a diameter or length and width of 0.5-0.8 mm, a height of 0.8-1.5 mm, and a center-to-center spacing of 1-1.5 mm.

[0040] The magnetic conductor nail posts 11 are provided below the radiation slot 10 along the signal transmission direction. A nail post group 111 consisting of 6 magnetic conductor nail posts 11 (3 on each side) is provided. The number of nail post groups 111 is equal to the number of radiation slots 10 and corresponds one to one.

[0041] In the signal transmission direction: the first group of nail column groups 111 is aligned with the magnetic conductor nail column 11 at the signal input end; the center of the first radiation slot 10 corresponding to the first group of nail column groups 111 is offset to one side of the center of the first group of nail column groups 111, and the second radiation slot 10 is aligned with the center of the first radiation slot 10 or has a small offset; the second group of nail column groups 111 is offset as a whole by a certain distance, so that the center of the second radiation slot 10 and the center of the second group of nail column groups 111 are offset to the other side; the subsequent nail column groups 111 and radiation slots 10 are arranged in a staggered manner in a similar manner; an end nail column group 112 is set at the end of the last group of nail column groups 111. Depending on the size, the end nail column group 112 consists of 2-3 magnetic conductor nail columns 11, and the distance from the end nail column group 112 to the center of the last group of nail column groups 111 is approximately 1 / 4 of the waveguide wavelength.

[0042] By adjusting the center spacing (approximately 1 / 2 of the waveguide wavelength) and offset of adjacent nail column groups 111, the offset of the corresponding radiation slot 10 relative to the column group 111 can be close to or satisfy the Taylor distribution or Chebyshev distribution, which facilitates the optimization of the directivity and sidelobe suppression of the slot array.

[0043] Below the waveguide antenna 1, a shielding wall 12 is provided on the outside of the magnetic conductor nail post 10 (including the nail post group 111 and the end nail post group 112); the shielding wall 12 is the same height as the magnetic conductor nail post, with a width of 0.5-0.8 mm, and a center distance of 1-1.5 mm from the magnetic conductor nail post 10, the nail post group 111 and the end nail post group 112.

[0044] The PCB main board 2 includes at least a metallized layer 21 and a dielectric material 22 on the top surface; the metallized layer 21 covers all or part of the dielectric material 22, facing the waveguide antenna 1; the metallized layer 21 is combined with the magnetic conductor nail post 10 (including the nail post group 111 and the end nail post group 112) and the shielding wall 12 to form a waveguide transmission cavity 30.

[0045] The magnetic conductor pins 10 and shielding wall 12 form the two E-surface side surfaces and two end surfaces of the waveguide transmission cavity 30. The waveguide antenna 1 forms the H-surface top surface of the waveguide transmission cavity 30. The metallization layer 21 forms the H-surface bottom surface of the waveguide transmission cavity 30. The coverage area of ​​the metallization layer 21 is greater than or equal to the total projected area of ​​the magnetic conductor pins 10 (including the pin group 111 and the end pin group 112) and the shielding wall 12. The metallization layer 21 and the waveguide antenna 1 can be in contact or with a certain amount of clearance.

[0046] In a preferred embodiment, according to actual conditions, a ridge 13 is provided in the center of the waveguide transmission cavity 30 below the waveguide antenna 1; the ridge 13 is evenly arranged in the waveguide transmission cavity 30, with a height of 0.5-0.8 mm and a width of 0.5-0.8 mm; no ridge 13 is provided in the middle of the nail column group 111; as a transition, in the area close to the first group of nail column groups 111, the height of the ridge 13 gradually decreases until it is 0.

[0047] The radiation slot 10 is divided into a lower radiation slot 101 and an upper radiation slot 102; in the direction of signal transmission: the lower radiation slot 101 and the upper radiation slot 102 are symmetrical on the left and right, with the same front and rear lengths (1.8-2.2mm), and heights of 0.7-1.3mm respectively; the lower radiation slot 101 and the upper radiation slot 102 have different left and right widths, the lower radiation slot 101 has a smaller width, between 0.8-1.2mm, and is mainly used to debug the S parameters of the slot array (such as standing wave, impedance, etc.); the upper radiation slot 102 has a larger width, between 2.5-5mm, and can be made into bevels on both sides, which is mainly used to debug the directionality of the slot array (such as normal gain, beam width, etc.).

[0048] The waveguide antenna 1 is made of metal or plastic with a metallized surface.

[0049] In one embodiment of the present invention, a center frequency of 77 GHz and a -10 dB relative bandwidth of 6.7 GHz are achieved (refer to Figure 5As shown), normal gain greater than 14dBi (refer to Figure 6 As shown in the figure), the sidelobe suppression effect exceeds -20dB, which can fully meet the application requirements of vehicle-mounted radar.

[0050] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0051] The above describes specific embodiments of the present invention. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art may make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. The embodiments of this application and the features in the embodiments may be combined with each other in any manner unless there is a conflict.

Claims

1. A radiation slot structure suitable for a waveguide antenna, characterized in that: include: A waveguide antenna (1), wherein the waveguide antenna (1) has a waveguide transmission cavity (30); One or more radiation slots (10) are provided through the top of the waveguide antenna (1), and a magnetic conductor nail post (11) is provided on the top surface of the H-surface of the waveguide transmission cavity (30). The magnetic conductor nail posts (11) are provided on both sides of the radiation slot (10) along the signal transmission direction to form a nail post group (111), and the geometric center of the nail post group (111) is offset from the geometric center of the radiation slot (10).

2. The radiation slot structure suitable for a waveguide antenna according to claim 1, characterized in that: The number of the nail column groups (111) and the number of the radiation gaps (10) are equal and arranged in a one-to-one correspondence; The geometric centers of two adjacent nail column groups (111) are offset from each other, and the geometric centers of multiple nail column groups (111) are staggered.

3. The radiation slot structure suitable for a waveguide antenna according to claim 1, characterized in that: The magnetic conductor nail post (11) is also arranged at the end of the last nail post group (111) along the signal transmission direction to form an end nail post group (112); The distance between the end nail column group (112) and the center of the last nail column group (111) is 1 / 4 of the waveguide wavelength.

4. The radiation slot structure suitable for a waveguide antenna according to claim 2, characterized in that: The center spacing and offset of adjacent nail column groups (111) make the offset of the corresponding radiation slot (10) relative to the nail column group (111) close to or satisfy Taylor distribution or Chebyshev distribution.

5. The radiation slot structure suitable for a waveguide antenna according to claim 1, characterized in that: A shielding wall (12) is also provided on the top surface of the H-surface of the waveguide transmission cavity (30), and the shielding wall (12) is located outside the magnetic conductor nail column (11).

6. The radiation slot structure suitable for a waveguide antenna according to claim 1, characterized in that: Also includes a PCB main board (2); The PCB mainboard (2) comprises a metallization layer (21) and a dielectric material (22) located on the top surface, wherein the metallization layer (21) completely or partially covers the dielectric material (22); The metallized layer (21), the magnetic conductor nail post (11), the waveguide antenna (1) and the shielding wall (12) surround and form a waveguide transmission cavity (30); the magnetic conductor nail post (11) and the shielding wall (12) constitute two E-surface side surfaces and two end faces of the waveguide transmission cavity (30); the waveguide antenna (1) constitutes the H-surface top surface of the waveguide transmission cavity (30); and the metallized layer (21) constitutes the H-surface bottom surface of the waveguide transmission cavity (30).

7. The radiation slot structure suitable for a waveguide antenna according to claim 1, characterized in that: The radiation slot (10) comprises a lower radiation slot (101) and an upper radiation slot (102); the lower radiation slot (101) and the upper radiation slot (102) are arranged symmetrically along the signal transmission direction, and have the same length in front and back; the width of the lower radiation slot (101) is smaller than the width of the upper radiation slot (102).

8. A waveguide transmission line, characterized in that: The invention comprises a radiation slot structure suitable for a waveguide antenna according to any one of claims 1 to 7.

9. A waveguide antenna (1) radar, characterized in that Comprising the waveguide transmission line according to claim 8.

10. An automobile, characterized in that: A radar comprising the waveguide antenna (1) as claimed in claim 9.

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