Bottom feed cavity array antenna and millimeter wave radar device

Abstract

The invention discloses a bottom feed cavity array antenna and a millimeter wave radar device, and belongs to the technical field of antennae, the bottom feed cavity array antenna comprises an antenna port, a transition section, a cavity and a bottom feed waveguide; the lower end of the cavity is fixedly connected with the bottom feed waveguide; the upper end of the cavity is connected with an antenna port through a transition section; the number of the transition sections is one or more, and the number of the antenna ports is one or more. The transmission channels formed in the transition section and the antenna through grooves formed in the antenna opening are in one-to-one correspondence up and down and are communicated with each other, and the transition section is communicated with the cavity. Through the mode, waveguide feeding is adopted, so that the loss of a feeding link is greatly reduced; coplanar design with a radar chip is not needed, layered design with the radar chip can be achieved, and the radar size is effectively reduced; according to the invention, the working bandwidth is relatively wide.

Description

Technical Field

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

[0002] Millimeter-wave radar is a radar that works in the millimeter-wave band. The frequency band is generally 30GHz to 300GHz, and the wavelength is 1 to 10mm, which is between microwaves and centimeter waves. Millimeter-wave radar has the characteristics of wide frequency band, short wavelength, narrow beam, light weight, strong resolution and strong penetration. Compared with microwaves, millimeter-wave radar has high resolution and a light and compact structure; compared with infrared and visible light, millimeter-wave radar has stronger penetration and is less affected by climate. It can ensure normal detection in harsh environments such as rain, snow, blizzards, smoke and dust, and has the characteristics of working all day and all night. These advantages make millimeter-wave radar one of the core sensors for advanced driver assistance and unmanned driving.

[0003] With the in-depth development of advanced driver assistance, vehicle-mounted millimeter-wave radar has also leaped from 3D radar to 4D imaging radar. On the basis of the original distance dimension, speed dimension, and azimuth dimension, the detection of the height dimension is added, which requires the radar to have more channels and higher resolution, and correspondingly, more radar antennas. However, the widely used microstrip array antenna still has the following defects:

[0004] 1. Microstrip array antennas are often fed by planar transmission lines, which have large dielectric losses;

[0005] 2. It needs to be designed coplanar with the radar chip. As the number of antennas increases, the size of the vehicle radar will inevitably increase;

[0006] 3. The bandwidth is narrow.

[0007] Based on this, the present invention designs a bottom-fed cavity array antenna and a millimeter-wave radar device to solve the above problems. Summary of the invention

[0008] In view of the above-mentioned shortcomings of the prior art, the present invention provides a bottom-fed cavity array antenna and a millimeter-wave radar device.

[0009] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0010] A bottom-fed cavity array antenna comprises an antenna port, a transition section, a cavity and a bottom-fed waveguide;

[0011] The lower end of the cavity is fixedly connected to the bottom-fed waveguide;

[0012] The upper end of the cavity is connected to the antenna port through a transition section;

[0013] There are one or more transition sections and one or more antenna ports;

[0014] The transmission channel opened in the transition section corresponds to the antenna through slot opened in the antenna port in a one-to-one manner and is connected to each other, and the transition section is connected to the cavity.

[0015] Furthermore, when there is one transition section, a plurality of transfer channels penetrating vertically are provided inside the transition section.

[0016] Furthermore, when there are multiple transition sections, a group of transfer channels penetrating vertically are opened inside each transition section.

[0017] Furthermore, when there is one antenna port, a plurality of antenna through slots penetrating vertically are provided inside the antenna port.

[0018] Furthermore, when there are multiple antenna ports, a group of antenna through slots penetrating vertically are provided inside each antenna port.

[0019] Furthermore, the number of transmission channels is consistent with the number of antenna slots and corresponds one to one up and down, the upper end of each transmission channel is connected to the antenna slot above it, and the lower end of the transmission channel is connected to the cavity.

[0020] Furthermore, the antenna port is a 1×N array antenna port, wherein 2≤N≤16; N represents the number of antenna slots.

[0021] Furthermore, the cavity and the curved metal waveguide both have a wide side and a narrow side, and the wide side of the cavity is arranged in parallel with the narrow side of the bottom-fed waveguide or the narrow side of the cavity is arranged in parallel with the wide side of the curved metal waveguide.

[0022] Furthermore, the antenna port, transition section, cavity and bottom-fed waveguide are integrally formed.

[0023] Furthermore, a millimeter wave radar device comprises the bottom-fed cavity array antenna and a millimeter wave radar board as described in the claim, wherein the millimeter wave radar board is connected to the bottom-fed waveguide.

[0024] Beneficial Effects

[0025] The present invention adopts waveguide feeding, which greatly reduces the feeder link loss;

[0026] The present invention does not need to be designed on the same plane as the radar chip, but can be designed in layers with the radar chip, effectively reducing the size of the radar;

[0027] The working bandwidth of the present invention is relatively wide;

[0028] The invention has a simple structure and low requirements on processing precision, which is beneficial to improving the production yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 The bottom-fed cavity array antenna of the present invention is a three-dimensional Figure 1 ;

[0031] Figure 2 It is a front view of the bottom-fed cavity array antenna of the present invention;

[0032] Figure 3 It is a left side view of the bottom-fed cavity array antenna of the present invention;

[0033] Figure 4 For along Figure 2 AA direction cross-sectional view;

[0034] Figure 5 For along Figure 3 BB direction cross-sectional view;

[0035] Figure 6 It is a structural stereogram of a bottom-fed cavity array antenna of the present invention when there is one antenna port;

[0036] Figure 7 It is a structural stereogram of the bottom-fed cavity array antenna of the present invention when there are six antenna ports;

[0037] Figure 8 is a plan view of the bottom-fed cavity array antenna of the present invention;

[0038] Fig. 9 It is a structural stereogram of the millimeter wave radar device of the present invention.

[0039] The numbers in the figure represent:

[0040] 1. Antenna port 2. Transition section 3. Cavity 4. Bottom-fed waveguide 5. Millimeter-wave radar board 6. Antenna slot 7. Transmission channel. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] The present invention will be further described below in conjunction with the embodiments.

[0043] Example 1

[0044] Please refer to the instruction manual Figure 1-9 As shown, a bottom-fed cavity array antenna includes an antenna port 1, a transition section 2, a cavity 3 and a bottom-fed waveguide 4;

[0045] The lower end of the cavity 3 is fixedly connected to the bottom-fed waveguide 4;

[0046] The upper end of the cavity 3 is connected to the antenna port 1 through the transition section 2;

[0047] There are one or more transition sections 2 and one or more antenna ports 1;

[0048] The transmission channel 7 opened inside the transition section 2 corresponds to the antenna through slot 6 opened inside the antenna port 1 in a one-to-one manner and is connected to each other, and the transition section 2 is connected to the cavity 3 .

[0049] The transition section 2 converts the electromagnetic wave signal propagating in the waveguide into a specific electromagnetic field distribution, and distributes the electromagnetic wave signal to the antenna port 1 through the transition component.

[0050] Please refer to the instruction manual Figure 6 When there is one antenna port 1, a plurality of antenna slots 6 are provided inside the antenna port 1 and run through the antenna port 1 vertically;

[0051] When there are multiple antenna ports 1, each antenna port 1 has a group of antenna slots 6 extending vertically therethrough.

[0052] The number of the transmission channels 7 is consistent with the number of the antenna slots 6 and corresponds one to one up and down. The upper end of each transmission channel 7 is connected to the antenna slot 6 above it, and the lower end of the transmission channel 7 is connected to the cavity 3;

[0053] Antenna port 1 is arranged in a straight line, and its function is to radiate the radar signal generated by the millimeter wave radar board into the free space and receive the electromagnetic waves in the space; by adjusting the size of antenna port 1, the gain, horizontal plane beam and elevation plane beam of the array antenna can be adjusted;

[0054] The antenna ports 1 of the array antenna may be arranged separately from each other, or may be connected together to form an integral antenna port 1;

[0055] The function of the transition section 2 is to achieve impedance matching between the cavity 3 and the antenna port 1 during electromagnetic wave propagation; by adjusting the size of the transition section 2, a good matching between the cavity 3 and the antenna 1 can be achieved;

[0056] The function of the cavity 3 is to convert the electromagnetic wave signal propagating in the waveguide into a specific electromagnetic field distribution, and distribute the electromagnetic wave signal through the transition section 2 to the multiple antenna slots 6 of the antenna port 1;

[0057] The bottom-fed waveguide 4 feeds the radar signal generated by the millimeter-wave radar board 5 into the cavity 3, so as to be transmitted to the antenna port 1 for radiation, and transmits the signal received by the antenna to the millimeter-wave radar board 5;

[0058] During the transmission process, the high-frequency millimeter wave signal passes through the millimeter wave radar board 5 to the bottom feed waveguide 4, then to the cavity 3, then to the transition section 2, and finally radiates to the free space through the antenna port 1;

[0059] The receiving process is exactly the opposite of the sending process. The millimeter wave signal goes from the free space to the antenna port 1, then to the transition section 2, then to the cavity 3, then through the bottom-fed waveguide 4, and finally to the millimeter wave radar board 5.

[0060] The present invention adopts waveguide feeding, which greatly reduces the feeder link loss;

[0061] The present invention does not need to be designed on the same plane as the radar chip, but can be designed in layers with the radar chip, effectively reducing the size of the radar;

[0062] The working bandwidth of the present invention is relatively wide;

[0063] The invention has a simple structure and low requirements on processing precision, which is beneficial to improving the production yield.

[0064] Example 2

[0065] Please refer to the instruction manual Fig. 9 , a millimeter wave radar device, comprising the bottom-fed cavity array antenna and the millimeter wave radar board 5 in embodiment 1;

[0066] The millimeter wave radar board 5 is used to generate radar signals and transmit them to the bottom-fed waveguide 4, and receive radar signals conducted by the bottom-fed waveguide 4;

[0067] During the transmission process, the high-frequency millimeter wave signal passes through the millimeter wave radar board 5 to the bottom feed waveguide 4, then to the cavity 3, then to the transition section 2, and finally radiates to the free space through the antenna port 1;

[0068] The receiving process is exactly the opposite of the sending process. The millimeter wave signal goes from the free space to the antenna port 1, then to the transition section 2, then to the cavity 3, then through the bottom-fed waveguide 4, and finally to the millimeter wave radar board 5.

[0069] Example 3

[0070] Please refer to the instruction manual Figure 7 Preferably, the antenna port 1 is a 1×N array antenna port, where 2≤N≤16; N represents the number of antenna slots 6;

[0071] Figure 7 The structural schematic diagram of the bottom-fed cavity array antenna with 1×6 cavity array antenna ports is shown in FIG.

[0072] Example 4

[0073] Please refer to the instruction manual Figure 8 Preferably, the antenna port 1, the transition section 2, the cavity 3 and the bottom-fed waveguide 4 are integrally formed.

[0074] The curved metal waveguide 4 is fixedly mounted on the bottom end of the cavity 3, and the millimeter wave radar antenna is processed in one piece. When processing the bottom-fed cavity array antenna, it needs to be divided into at least three layers, and the dividing lines A and B are the processing section direction curves. The advantage is that the antenna and the feeding waveguide are designed in layers, which saves space and is suitable for the application of large millimeter wave radar antenna arrays.

[0075] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A bottom-fed cavity array antenna, comprising an antenna port (1), characterized in that: It also includes a transition section (2), a cavity (3) and a bottom-fed waveguide (4); The lower end of the cavity (3) is fixedly connected to the bottom-fed waveguide (4); The upper end of the cavity (3) is connected to the antenna port (1) via a transition section (2); There are one or more transition sections (2), and there are one or more antenna ports (1); The transmission channel (7) opened inside the transition section (2) and the antenna through slot (6) opened inside the antenna port (1) correspond one to another and are connected to each other, and the transition section (2) is connected to the cavity (3).

2. The bottom-fed cavity array antenna according to claim 1, characterized in that: When there is one transition section (2), a plurality of groups of transmission channels (7) penetrating vertically are provided inside the transition section (2).

3. The bottom-fed cavity array antenna according to claim 1, characterized in that: When there are a plurality of transition sections (2), a group of transmission channels (7) penetrating vertically are provided inside each transition section (2).

4. The bottom-fed cavity array antenna according to claim 2, characterized in that: When there is one antenna port (1), a plurality of groups of antenna through slots (6) penetrating vertically are provided inside the antenna port (1).

5. The bottom-fed cavity array antenna according to claim 3, characterized in that: When there are a plurality of antenna ports (1), each antenna port (1) is provided with a group of antenna through slots (6) penetrating vertically.

6. The bottom-fed cavity array antenna according to claim 5, characterized in that: The number of the transmission channels (7) is consistent with the number of the antenna slots (6) and corresponds one to one up and down; the upper end of each transmission channel (7) is connected to the antenna slot (6) above it, and the lower end of the transmission channel (7) is connected to the cavity (3).

7. The bottom-fed cavity array antenna according to claim 6, characterized in that: The antenna port (1) is a 1×N array antenna port, wherein 2≤N≤16; N represents the number of antenna slots (6).

8. The bottom-fed cavity array antenna according to claim 7, characterized in that: The cavity (3) and the curved metal waveguide tube (4) both have a wide side and a narrow side, and the wide side of the cavity (3) and the narrow side of the bottom-fed waveguide (4) are arranged in parallel, or the narrow side of the cavity (3) and the wide side of the curved metal waveguide tube (4) are arranged in parallel.

9. The bottom-fed cavity array antenna according to claim 8, characterized in that The antenna port (1), transition section (2), cavity (3) and bottom-feed waveguide (4) are integrally formed.

10. A millimeter wave radar device, characterized in that: It comprises the bottom-fed cavity array antenna as claimed in claim 9 and a millimeter-wave radar board (5), wherein the millimeter-wave radar board (5) is connected to the bottom-fed waveguide (4).

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