Broadband 4T4R automobile radar antenna

Abstract

A broadband 4T4R automobile radar antenna disclosed by the present invention comprises an upper-layer radiation plate and a lower-layer feed plate, the upper-layer radiation plate is provided with a plurality of horn mouths and a plurality of EBG choke grooves, the horn mouths and the EBG choke grooves are distributed at intervals in a staggered manner, each horn mouth is internally provided with a plurality of radiation slots at unequal intervals, and the upper-layer radiation plate is provided with a plurality of feed slots. A waveguide feed port is arranged on the lower surface of the lower layer feed panel; compared with the prior art, in order to ensure the antenna gain, the choke design in the EBG form is adopted between the antenna units, the transmission of surface waves is effectively restrained, and the isolation degree between the antenna units is improved; the horizontal plane realizes a good gain effect by accurately optimizing taper pin distribution of the slot array and amplitude-phase excitation of the feed network, and has better sidelobe envelope directional diagram characteristics; and the width of the lobe on the horizontal plane is adjusted by adjusting the inclination angle of the horn mouth, so that the width reaches 63 + / -3 degrees, and the gain effect is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of automobile radar antennas, in particular to a broadband 4T4R automobile radar antenna. Background Art

[0002] As autonomous driving technology brings more and more comfortable experiences to people, antennas, as the main body of transmission and reception, have emerged to help radars quickly and accurately obtain physical environment information around the vehicle body. Among them, waveguide slot antennas have been widely used in radar and communication systems due to their compact structure, large power capacity, precise control of aperture distribution, and ease of achieving low side lobes. Using low-loss waveguide feeding, this type of antenna has been proven to have high radiation efficiency.

[0003] At present, the original wide-band automotive radar antenna has a frequency band of 76-79 GHz, which is relatively small. The size design conditions of the automotive radar antenna are limited. How to improve the radiation efficiency and gain of the antenna under the condition of limited antenna design area is an urgent problem to be solved. To this end, the present invention proposes a wide-band 4T4R automotive radar antenna. Summary of the invention

[0004] The object of the present invention is to provide a wide-band 4T4R automotive radar antenna to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a wide-band TR automobile radar antenna, comprising an upper radiation plate and a lower feeding plate, the upper radiation plate is provided with a plurality of horns and a plurality of EBG choke slots, and the horns and the EBG choke slots are staggered and spaced, each of the horns is provided with a plurality of radiation slots with unequal intervals, a waveguide feeding port is provided on the lower surface of the lower feeding plate, and a plurality of waveguide feeding input ports penetrating the lower feeding plate are provided in the waveguide feeding port, an air waveguide network connected to the horn is provided on the lower surface of the upper radiation plate, the lower feeding plate is located below the upper radiation plate, a feeding network corresponding to the position of the air waveguide network and a feeding connection port corresponding to the position of the horn are provided on the upper surface of the lower feeding plate, and an end of the feeding network away from the feeding connection port is connected to the waveguide feeding input port.

[0006] As a preferred technical solution of the present invention, the number of the bell mouths is eight, and the eight bell mouths are port No. 1, port No. 2, port No. 3, port No. 4, port No. 5, port No. 6, port No. 7, and port No. 8.

[0007] As a preferred technical solution of the present invention, the size of the bell mouth is 15.6*3.2*2.1 mm.

[0008] As a preferred technical solution of the present invention, the vertical section of the bell mouth is an isosceles trapezoidal structure, the longer bottom side of the isosceles trapezoid is the upper base, and the angle between the upper base and the waist is α.

[0009] As a preferred technical solution of the present invention, the angle α of port No. 1, port No. 2, port No. 3, port No. 4, port No. 6, port No. 7, and port No. 8 is sixty-eight degrees, and the angle α of port No. 5 is seventy-one degrees.

[0010] As a preferred technical solution of the present invention, the number of the radiation slots is four, and the four radiation slots are radiation port No. 1, radiation port No. 2, radiation port No. 3, and radiation port No. 4 from left to right or from right to left, and the amplitude distribution ratio of radiation port No. 1, radiation port No. 2, radiation port No. 3, and radiation port No. 4 is 0.5607:1:1:0.5607.

[0011] As a preferred technical solution of the present invention, the number of the EBG choke slots is ten, and the ten EBG choke slots are respectively a first choke slot, a second choke slot, a third choke slot, a fourth choke slot, a fifth choke slot, a sixth choke slot, a seventh choke slot, an eighth choke slot, a ninth choke slot, and a tenth choke slot, wherein the eighth choke slot and the ninth choke slot are of a Z-shaped structure.

[0012] As a preferred technical solution of the present invention, a plurality of bumps are arranged in an array inside each EBG choke slot.

[0013] As a preferred technical solution of the present invention, the size of each of the bumps is 0.83 mm*0.83 mm*1.2 mm, and the spacing between adjacent bumps is periodically distributed in the size of 1.2 mm*1.92 mm.

[0014] As a preferred technical solution of the present invention, a plurality of choke blocks are further provided in the waveguide feeding port.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] The invention discloses a wideband 4T4R automobile radar antenna. In order to ensure the antenna gain, an EBG-type choke design is adopted between antenna units, which effectively curbs the transmission of surface waves and improves the isolation between antenna units. The horizontal plane achieves a good gain effect by accurately optimizing the cone pin distribution of the slot array and the amplitude and phase excitation of the feeding network, and has a better sidelobe envelope pattern characteristic. The horizontal plane lobe width is adjusted by adjusting the inclination angle of the horn mouth to reach 63°±3°, and the gain effect is effectively improved.

[0017] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0019] Figure 2 It is a schematic diagram of the top structure of the upper radiation plate of the present invention;

[0020] Figure 3 A top view of the upper radiation plate of the present invention;

[0021] Figure 4 For the present invention Figure 3 Sectional view of AA in the middle;

[0022] Figure 5 It is a schematic diagram of the structure of the upper radiation plate of the present invention when viewed from above;

[0023] Figure 6 It is a schematic diagram of the top view of the structure of the lower layer feeder board of the present invention;

[0024] Figure 7 It is a bottom view structural schematic diagram of the lower layer feeder board of the present invention;

[0025] Figure 8 This is a test diagram of the antenna unit standing wave ratio of the present invention;

[0026] Fig. 9 is the antenna unit linear array pattern of the present invention;

[0027] Fig.10 It is the antenna array standing wave ratio test diagram of the present invention;

[0028] Fig.11 is the excitation direction diagram of port No. 1 of the present invention;

[0029] Fig.12 is the excitation pattern of port No. 2 of the present invention;

[0030] Fig.13 is the excitation pattern of port No. 3 of the present invention;

[0031] Fig.14 is the excitation pattern of port No. 4 of the present invention;

[0032] Fig.15 is the excitation pattern of port No. 5 of the present invention;

[0033] Fig.16 is the excitation pattern of port No. 6 of the present invention;

[0034] Fig.17 is the excitation pattern of port No. 7 of the present invention;

[0035] Fig.18is the excitation pattern of port No. 8 of the present invention;

[0036] In the figure: 10, upper radiation plate; 11, bell mouth; 111, port 1; 112, port 2; 113, port 3; 114, port 4; 115, port 5; 116, port 6; 117, port 7; 118, port 8; 12, EBG choke slot; 121, first choke slot; 122, second choke slot; 123, third choke slot; 124, fourth choke slot; 125, fifth choke slot; 126, sixth choke slot; 12 7. The seventh choke slot; 128. The eighth choke slot; 129. The ninth choke slot; 120. The tenth choke slot; 13. Radiation gap; 131. Radiation port No. 1; 132. Radiation port No. 2; 133. Radiation port No. 3; 134. Radiation port No. 4; 14. Bump; 15. Air waveguide network; 16. Mounting hole; 20. Lower layer feeding board; 21. Waveguide feeding port; 211. Waveguide feeding input port; 22. Choke block; 23. Feeding network; 24. Feeding connection port. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions 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 ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] In the description of the present invention, it should be noted that the terms "vertical", "up", "down", "horizontal", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 the present invention.

[0039] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" 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 or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. It should be noted that the H plane in this application is a horizontal plane, the E plane is a vertical plane, and the V plane is also a vertical plane, that is, a narrow plane.

[0040] See also Figure 1-18In this embodiment, a wideband 4T4R automotive radar antenna is provided, including an upper radiation plate 10 and a lower feeding plate 20. The upper radiation plate 10 is provided with a plurality of horns 11 and a plurality of EBG choke slots 12, and the horns 11 and the EBG choke slots 12 are arranged at staggered intervals, and each horn 11 is provided with a plurality of radiation slots 13 with unequal intervals, and the lower surface of the lower feeding plate 20 is provided with a waveguide feeding port 21, and the waveguide feeding port 21 is provided with a plurality of through-holes 13. The waveguide feed input port 211 of the lower feeding board 20 is passed through, the lower surface of the upper radiation board 10 is provided with an air waveguide network 15 connected to the horn mouth 11, the lower feeding board 20 is located below the upper radiation board 10, and the upper surface of the lower feeding board 20 is provided with a feeding network 23 corresponding to the position of the air waveguide network 15 and a feeding connection port 24 corresponding to the position of the horn mouth 11, and the feeding network 23 is far from the feeding connection port 24. The end of the feeding network 23 is connected to the waveguide feed input port 211. The feeding network adopts the form of air waveguide. In order to minimize the electromagnetic wave leakage caused by assembly and welding, since the middle current is relatively small, we adopt the form of middle splitting of the air waveguide. There are four radiation slots 13. The four radiation slots 13 are respectively radiation port 131, radiation port 132, radiation port 133 and radiation port 134 from left to right or from right to left. The amplitude distribution ratio of radiation port 131, radiation port 132, radiation port 133 and radiation port 134 is 0.5607:1:1:0.5607. The length of the radiation slot 13 is 2.05mm and the width is 1.15mm. The radiation slot adopts unequally spaced series feeding to obtain the corresponding amplitude and phase distribution, which meets the requirement that the side lobe is lower than -20. The horizontal plane achieves good gain effect by accurately optimizing the cone pin distribution of the slot array and the amplitude and phase excitation of the feeding network, and has better side lobe envelope pattern characteristics.

[0041] A total of eight 4T4R units are used as the antenna array. In order to meet the requirements of the far-field transmitting antenna gain and the 3dB beam width index of the vertical section, a single vertical section antenna is designed with four radiation slots with a length of 2.05mm and a width of 1.15mm. In order to achieve the effect of low sidelobe, the radiation slot period is designed with unequal spacing period so that the radiation slot meets the cone pin distribution.

[0042] In this embodiment, the number of bell mouths 11 is eight, and the eight bell mouths 11 are port No. 1 111, port No. 2 112, port No. 3 113, port No. 4 114, port No. 5 115, port No. 6 116, port No. 7 117, and port No. 8 118. The size of the bell mouth 11 is 15.6*3.2*2.1mm, and the vertical section shape of the bell mouth 11 is an isosceles trapezoidal structure. The longer bottom side of the isosceles trapezoid is the upper base, and the angle between the upper base and the waist is α. The angle α of port No. 1 111, port No. 2 112, port No. 3 113, port No. 4 114, port No. 6 116, port No. 7 117, and port No. 8 118 is sixty-eight degrees, and the angle α of port No. 5 115 is seventy-one degrees. The horizontal lobe width is adjusted by adjusting the inclination angle of the bell mouth to reach 63°±3°, and the gain effect is effectively improved.

[0043] In this embodiment, the number of EBG choke slots 12 is ten, and the ten EBG choke slots 12 are respectively a first choke slot 121, a second choke slot 122, a third choke slot 123, a fourth choke slot 124, a fifth choke slot 125, a sixth choke slot 126, a seventh choke slot 127, an eighth choke slot 128, a ninth choke slot 129, and a tenth choke slot 120, wherein the eighth choke slot 128 and the ninth choke slot 129 are Z-shaped structures.

[0044] Specifically, the design dimensions of the ten choke slots, namely the first choke slot 121, the second choke slot 122, the third choke slot 123, the fourth choke slot 124, the fifth choke slot 125, the sixth choke slot 126, the seventh choke slot 127, the eighth choke slot 128, the ninth choke slot 129 and the tenth choke slot 120 are respectively: 15.7*6*1.2mm, 15.7*6*1.2mm, 15.7*4*1.2mm, 15.7*6*1.2mm, 15.7*6*1.2mm, 15.7*2*1.2mm, 15.7*11.9*1.2mm, 18*10*1.2mm, 26*8*1.2mm and 15.7*2*1.2mm.

[0045] A plurality of bumps 14 are arranged in an array inside each EBG choke slot 12 . The size of each bump 14 is 0.83 mm*0.83 mm*1.2 mm, and the spacing between adjacent bumps 14 is 1.2 mm*1.92 mm in a periodic distribution.

[0046] In order to ensure the antenna gain and prevent the E-plane beam from being affected by surface waves, an EBG-type choke design is used between antenna units, which effectively curbs the transmission of surface waves and improves the isolation between antenna units.

[0047] In this embodiment, a plurality of choke blocks 22 are further provided in the waveguide feeding port 21. The waveguide feeding port 21 also adopts an EBG structure to ensure that no leakage occurs with the waveguide chip.

[0048] In this embodiment, mounting holes 16 are provided on the upper radiation board 10 and the lower feeding board 20 , and the upper radiation board 10 and the lower feeding board 20 are soldered by solder paste, and the solder paste is located 1 mm outside the edge around the feeding network 23 .

[0049] Specifically, the antenna is divided into two layers, the upper plate includes part of the feed network, the radiation slot and the lobe adjustment horn, and the lower plate includes the feed input port and part of the waveguide feed network.

[0050] Between the upper and lower layers, solder paste is applied on the edges around the waveguide through the SMT process, and then it is installed on the customized welding tooling for SMT welding. The upper and lower layers are injection molded through high-precision molds; the material is injected at the molding site; the material undergoes a special plastic metallization process (PVD) to metalize its surface and make its surface roughness good; between the upper and lower layers, solder paste is applied on the outer side of the 1mm edge around one of the waveguide layers to ensure that the solder cannot enter the waveguide cavity after melting and affect the performance; precise positioning columns are used for positioning, and the upper and lower layers are assembled on the customized welding tooling for high-temperature welding.

[0051] The broadband 4T4R automotive radar antenna has been tested and tested with reference to the test Figure 8-10 , respectively, the antenna unit standing wave ratio test diagram, the antenna unit linear array directivity diagram and the antenna array standing wave ratio test diagram; among them, from Figure 8 According to the test results, the unit standing wave ratio is within 1.5, which meets the technical requirement of 1.8.

[0052] The test results of the antenna unit linear array pattern are shown in Table 1 below:

[0053] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value 14.92 -22dB 63°±4° 18°±1.5 76-81GHz

[0054] Table 1

[0055] The test results of the antenna array standing wave ratio test diagram are shown in Table 2 below:

[0056]

[0057]

[0058] Table 2 The test results of the excitation pattern of port No. 1 are shown in Table 3 below:

[0059] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value 15±1 -23dB 63°±2° 18°±1.5 76-81GHz

[0060] The test results of the excitation pattern of port No. 2 in Table 3 are shown in Table 4 below:

[0061] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value 15±1 -24dB 63°±2° 18°±1.5 76-81GHz

[0062] The test results of the excitation pattern of port No. 3 in Table 4 are shown in Table 5 below:

[0063] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value 15±1 -23dB 63°±2° 18°±1.5 76-81GHz

[0064] The test results of the excitation pattern of port No. 4 in Table 5 are shown in Table 6 below:

[0065] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value 15±1 -24dB 63°±2° 18°±1.5 76-81GHz

[0066] The test results of the excitation pattern of port 5 in Table 6 are shown in Table 7 below:

[0067] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value 15±1 -23dB 63°±2° 18°±1.5 76-81GHz

[0068] Table 7

[0069] The test results of the excitation pattern of port 6 are shown in Table 8 below:

[0070] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value 15±1 -24dB 63°±3° 18°±1.5 76-81GHz

[0071] Table 8

[0072] The test results of the excitation pattern of port 7 are shown in Table 9 below:

[0073] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value >15 -24dB 63°±4° 18°±1.5 76-81GHz

[0074] Table 9

[0075] The test results of the excitation pattern of port 8 are shown in Table 10 below:

[0076] Gain Side lobe H-plane beamwidth V-plane beam width Frequency band Technical requirements 15±1 -20dB 63°±4° 18°±1.5 76-81GHz Actual test value >15 -23dB 63°±4° 18°±1.5 76-81GHz

[0077] Table 10

[0078] According to Table 1-10 above and Figure 8-18 It can be seen that the actual test parameter values ​​of this wide-band 4T4R automotive radar antenna have met the technical requirements.

[0079] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A broadband 4T4R automotive radar antenna, characterized in that: The invention comprises an upper radiation plate (10) and a lower feeding plate (20), wherein the upper radiation plate (10) is provided with a plurality of bell mouths (11) and a plurality of EBG choke slots (12), and the bell mouths (11) and the EBG choke slots (12) are arranged at staggered intervals, and each of the bell mouths (11) is provided with a plurality of radiation slots (13) at unequal intervals, and the lower surface of the lower feeding plate (20) is provided with a waveguide feeding port (21), and the waveguide feeding port (21) is provided with a plurality of waveguide feeding input ports penetrating the lower feeding plate (20). (211), the lower surface of the upper radiation plate (10) is provided with an air waveguide network (15) connected to the bell mouth (11), the lower feeding plate (20) is located below the upper radiation plate (10), the upper surface of the lower feeding plate (20) is provided with a feeding network (23) corresponding to the position of the air waveguide network (15) and a feeding connection port (24) corresponding to the position of the bell mouth (11), and the end of the feeding network (23) away from the feeding connection port (24) is connected to the waveguide feeding input port (211).

2. A broadband 4T4R automotive radar antenna according to claim 1, characterized in that: The number of the bell mouths (11) is eight, and the eight bell mouths (11) are respectively port No. 1 (111), port No. 2 (112), port No. 3 (113), port No. 4 (114), port No. 5 (115), port No. 6 (116), port No. 7 (117), and port No. 8 (118).

3. The broadband 4T4R automotive radar antenna according to claim 2, characterized in that: The size of the bell mouth (11) is 15.6*3.2*2.1 mm.

4. The broadband 4T4R automotive radar antenna according to claim 2, characterized in that: The vertical section of the bell mouth (11) is in the shape of an isosceles trapezoidal structure, the longer bottom side of the isosceles trapezoid is the upper base, and the angle between the upper base and the waist is α.

5. The broadband 4T4R automotive radar antenna according to claim 4, characterized in that: The included angle α of the first port (111), the second port (112), the third port (113), the fourth port (114), the sixth port (116), the seventh port (117), and the eighth port (118) is sixty-eight degrees, and the included angle α of the fifth port (115) is seventy-one degrees.

6. The broadband 4T4R automotive radar antenna according to claim 1, characterized in that: The number of the radiation slots (13) is four, and the four radiation slots (13) are respectively a radiation port No. 1 (131), a radiation port No. 2 (132), a radiation port No. 3 (133), and a radiation port No. 4 (134) from left to right or from right to left, and the amplitude distribution ratio of the radiation port No. 1 (131), the radiation port No. 2 (132), the radiation port No. 3 (133), and the radiation port No. 4 (134) is 0.5607:1:1:0.5607.

7. The broadband 4T4R automotive radar antenna according to claim 1, characterized in that: The number of the EBG choke slots (12) is ten, and the ten EBG choke slots (12) are respectively a first choke slot (121), a second choke slot (122), a third choke slot (123), a fourth choke slot (124), a fifth choke slot (125), a sixth choke slot (126), a seventh choke slot (127), an eighth choke slot (128), a ninth choke slot (129), and a tenth choke slot (120), wherein the eighth choke slot (128) and the ninth choke slot (129) are of a Z-shaped structure.

8. The broadband 4T4R automotive radar antenna according to claim 1, characterized in that: A plurality of bumps (14) are arranged in an array inside each EBG choke slot (12).

9. The broadband 4T4R automotive radar antenna according to claim 8, characterized in that: The size of each of the protrusions (14) is 0.83 mm*0.83 mm*1.2 mm, and the spacing between adjacent protrusions (14) is periodically distributed at 1.2 mm*1.92 mm.

10. The broadband 4T4R automotive radar antenna according to claim 1, characterized in that: A plurality of choke blocks (22) are also provided in the waveguide feeding port (21).

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