Waveguide antenna

Abstract

The invention provides a waveguide antenna. The waveguide antenna comprises a radiant panel provided with two antenna beam adjusting units, a plurality of antenna units, a substrate integrated waveguide structure and an antenna matching section, the two antenna beam adjusting units are symmetrically arranged about the symmetry axis, and the multiple antenna units are arranged between the two antenna beam adjusting units in a staggered mode; a first distance which is 1 / 4 waveguide wavelength of a central frequency point is formed between a first center line of the antenna beam adjusting unit and the symmetry axis; a second interval which is 1 / 4 waveguide wavelength of the central frequency point is formed between the second center lines of two adjacent antenna units; the substrate integrated waveguide structure is provided with a pair of first metal column groups, and a third distance is formed between third center lines of the pair of first metal column groups; different fourth distances are formed between the fourth center lines of the plurality of antenna units and the symmetry axis, and the fourth distances are within the range of 10%-20% of the third distances; the antenna matching section is a three-section matching section, and the physical width of the antenna matching section is one fourth of the waveguide wavelength of a center frequency point.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of antennas, in particular to a waveguide antenna. BACKGROUND

[0002] With the rapid development of antennas in the application scenarios of missile-borne, airborne, ship-borne search and tracking, etc., the demand of users for high-gain and low-side lobe antennas is increasing.

[0003] The traditional parabolic antenna is difficult to make great improvement in high gain and low side lobe due to the limitation of its aperture, while the waveguide antenna has the advantages of high design flexibility, small insertion loss, high gain and easy to realize low amplitude lobe, which makes the waveguide antenna gradually replace the traditional parabolic antenna, so the waveguide antenna is more and more concerned by the society.

[0004] With more and more applications of waveguide antennas by users, the performance requirements of traditional waveguide antennas are more and more difficult to meet the use requirements of users, so how to realize the wideband high performance index requirements of traditional waveguide antennas has become a research and development trend. SUMMARY

[0005] The waveguide antenna provided by the present application aims to solve at least one of the defects of the existing waveguide antenna.

[0006] The present application provides a waveguide antenna. The waveguide antenna comprises: a radiation plate, wherein two antenna beam adjusting units, a plurality of antenna units, a substrate integrated waveguide structure and an antenna matching section are arranged on the radiation plate; The two antenna beam adjusting units are symmetrically arranged about a symmetry axis, and the plurality of antenna units are arranged in a staggered manner between the two antenna beam adjusting units; The first center line of any one of the antenna beam adjusting units and the symmetry axis have a preset first spacing, and the first spacing is one fourth of the waveguide wavelength formed by the waveguide antenna at the center frequency point of its working frequency band; The second center lines of the adjacent two antenna units have a preset second spacing, and the second spacing is one half of the waveguide wavelength formed by the waveguide antenna at the center frequency point of its working frequency band; The substrate integrated waveguide structure has a pair of first metal column groups, and the third center lines of the pair of first metal column groups have a preset third spacing; The fourth center lines of the plurality of antenna units and the symmetry axis have different fourth spacings, and the fourth spacings are within the range of 10% to 20% of the third spacing; The antenna matching section is a three-section matching section, and the physical width of the antenna matching section is one fourth of the waveguide wavelength formed by the waveguide antenna at the center frequency point of its working frequency band. Wherein, the axis of symmetry is parallel to the length direction of the antenna beam adjustment unit, the first center line, the third center line and the fourth center line are parallel to the axis of symmetry, and the second center line is perpendicular to the axis of symmetry.

[0007] In some embodiments, the radiating plate is further provided with a positioning boss, and the positioning boss, the substrate integrated waveguide structure and the antenna matching section are located on the same side surface of the radiating plate.

[0008] In some embodiments, the waveguide antenna further includes: The circuit board module and the metal fastener are provided, wherein the circuit board module is fitted to the positioning boss and the circuit board module is connected to the positioning boss by the metal fastener.

[0009] In some embodiments, the substrate integrated waveguide structure has a pair of second metal pillar groups, and the fifth center line of the second metal pillar groups is perpendicular to the axis of symmetry; A pair of first metal pillars and a pair of second metal pillars enclose a waveguide cavity, the antenna matching section is disposed in the waveguide cavity, and the antenna element passes through the radiating plate and is connected to the waveguide cavity.

[0010] In some embodiments, each of the first metal pillar groups is composed of M metal cylinders arranged along the length direction of the antenna beam adjustment unit at a preset fifth spacing; Each of the second metal pillar groups consists of N metal cylinders arranged along the width direction of the antenna beam adjustment unit at a preset fifth spacing; Each of the metal cylinders has a preset radius, and M is greater than N.

[0011] Preferably,

[0012] Where r is the radius of the metal cylinder. d is the waveguide wavelength of the substrate integrated waveguide structure, and d is the fifth spacing. The cutoff wavelength is the wavelength of the substrate integrated waveguide structure.

[0013] also,

[0014] Wherein, a refers to the third spacing, The free-space wavelength of the substrate-integrated waveguide structure is given. is the relative permittivity of the dielectric substrate of the substrate integrated waveguide structure.

[0015] In some embodiments,

[0016] in, The cutoff wavelength of the waveguide antenna is [wavelength value missing]. The waveguide wavelength of the waveguide antenna is given. λ is the free space wavelength of the waveguide antenna.

[0017] In some embodiments, the physical width of each antenna element is 0.6 mm to 1.5 mm; The physical length of each antenna element is half the free space wavelength formed by the waveguide antenna at the center frequency of its operating frequency band.

[0018] In some embodiments, the physical width of the antenna beam adjustment unit is 0.6 mm to 1.5 mm.

[0019] At least one beneficial effect of the waveguide antenna provided in this embodiment of the invention is that: A preset second spacing exists between the second center lines of two adjacent antenna elements in this waveguide antenna, and this second spacing is half the waveguide wavelength formed by the waveguide antenna at the center frequency point of its operating frequency band. This second spacing is used to adjust the phase of the antenna elements, adjust the sidelobes of the waveguide antenna, and adjust the beam pointing of the waveguide antenna. The substrate integrated waveguide structure in this waveguide antenna has a pair of first metal pillar groups, and a third spacing exists between the third center lines of the pair of first metal pillar groups. The fourth center lines of multiple antenna elements in this waveguide antenna have different fourth spacings with respect to the axis of symmetry, and the fourth spacing is within the range of 10% to 20% of the third spacing. This fourth spacing is used to adjust the amplitude of the antenna elements. The antenna matching section in this waveguide antenna is a three-section matching section, and the physical width of the antenna matching section is one-quarter of the waveguide wavelength formed by the waveguide antenna at the center frequency point of its operating frequency band. This three-section matching section design can extend the bandwidth of this waveguide antenna. In summary, the technical solution of this waveguide antenna can achieve the requirements of broadband high-performance indicators. Attached Figure Description

[0020] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0021] Figure 1 This is a schematic diagram of the waveguide antenna provided in an embodiment of the present invention; Figure 2 This is an exploded view of the waveguide antenna provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of the radiating plate, antenna beam adjustment unit, and antenna unit provided in the embodiments of the present invention; Figure 4This is a front view schematic diagram of the radiating plate, antenna beam adjustment unit, and antenna unit provided in the embodiments of the present invention; Figure 5 This is a schematic diagram of the structure of the radiating plate, antenna unit, metal cylinder, waveguide cavity, antenna matching section and positioning boss provided in the embodiments of the present invention; Figure 6 This is a front view schematic diagram (I) of the radiating plate, antenna unit, metal cylinder, waveguide cavity, antenna matching section and positioning boss provided in the embodiment of the present invention; Figure 7 This is a front view schematic diagram of the radiating plate, antenna unit, substrate integrated waveguide structure, antenna matching section and positioning boss provided in the embodiments of the present invention; Figure 8 This is a front view schematic diagram of the radiating plate, antenna unit, first metal column group, second metal column group, third metal column group, antenna matching section and positioning boss provided in the embodiment of the present invention; Figure 9 This is a front view (II) of the radiating plate, antenna unit, metal cylinder, waveguide cavity, antenna matching section and positioning boss provided in the embodiment of the present invention; Figure 10 This is a schematic diagram of the simulation results of waveguide antenna return loss provided in an embodiment of the present invention; Figure 11 This is a schematic diagram of the waveguide antenna gain simulation results provided in an embodiment of the present invention; Figure 12 This is a schematic diagram of the simulation results of the waveguide antenna at 75G frequency PHi=0° section provided in the embodiment of the present invention; Figure 13 This is a schematic diagram of the simulation results of the waveguide antenna at 75G frequency PHi=90° section provided in the embodiment of the present invention; Figure 14 This is a schematic diagram of the simulation results of the waveguide antenna at 78.5G frequency PHi=0° section provided in the embodiment of the present invention; Figure 15 This is a schematic diagram of the simulation results of the waveguide antenna at a frequency of 78.5G with a PHi=90° cross section provided in this embodiment of the invention; Figure 16 This is a schematic diagram of the simulation results of the waveguide antenna at 82G frequency PHi=0° section provided in the embodiment of the present invention; Figure 17 This is a schematic diagram of the simulation results of the waveguide antenna at 82G frequency PHi=90° section provided in the embodiment of the present invention.

[0022] Reference numerals: 100, waveguide antenna; 1001, axis of symmetry; 1, radiating plate; 11, antenna beam adjustment unit; 111, first center line; d1, first spacing; 12, antenna element; 121, second center line; 122, fourth center line; d2, second spacing; d3, fourth spacing; 13, substrate integrated waveguide structure; 131, first metal pillar group; 132, second metal pillar group; 133, third metal pillar group; 1301, metal cylinder; 1302, waveguide cavity; 1311, third center line; a, third spacing; d, fifth spacing; 14, antenna matching section; 15, positioning boss; 2, circuit board module; 3, metal fastener. Detailed Implementation

[0023] The present invention will now be described in detail with reference to specific embodiments. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope and application of the present invention.

[0024] It should be noted that, unless otherwise expressly specified and limited, the terms "perpendicular to," "parallel to," "length direction," "width direction," etc., used in this specification indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. The terms "installed," "connected," "linked," "fixed," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; a direct connection or an indirect connection through an intermediate medium. Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," "third," or "fourth" may explicitly or implicitly include one or more of that feature; "a plurality" or "several" means two or more; and "and / or" includes any and all combinations of one or more of the associated listed items. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] The term "beamwidth" refers to the width of the main lobe of a waveguide antenna, defined as the angle at which the power drops to half of its maximum value (i.e., -3dB), and beamwidth is divided into horizontal beamwidth and vertical beamwidth.

[0026] Please see Figures 1-9 The waveguide antenna 100 includes: a radiating plate 1.

[0027] Specifically, the radiating plate 1 is provided with two antenna beam adjustment units 11, multiple antenna units 12, a substrate integrated waveguide structure 13, and an antenna matching section 14.

[0028] To further explain, the radiating plate 1, the substrate integrated waveguide structure 13, and the antenna matching section 14 can be made from a single piece of metal, or from a single piece of plastic after metallization.

[0029] In this embodiment, the waveguide antenna 100 uses plastic metallization to replace the metal block and uses a substrate integrated waveguide (SIW) structure 13 to transmit signals. This design not only reduces weight but also reduces production costs without affecting the performance of the waveguide antenna 100, making it more advantageous in the market.

[0030] It should be noted that the substrate integrated waveguide structure 13 includes at least a pair of first metal pillar groups 131, a pair of second metal pillar groups 132 and a pair of third metal pillar groups 133, and the first metal pillar group 131, the second metal pillar group 132 and the third metal pillar group 133 are all composed of multiple metal cylinders 1301 arranged in a preset periodic pattern.

[0031] The shape formed by the pair of first metal pillar groups 131 and the pair of second metal pillar groups 132 is rectangular, and a waveguide cavity 1302 is formed inside the rectangle.

[0032] In addition, a pair of first metal pillars 131 serve as the long side of the rectangle, while a pair of second metal pillars 132 serve as the short side of the rectangle.

[0033] In addition, a pair of third metal pillar groups 133 are disposed on the outside of the rectangle and are parallel to the pair of first metal pillar groups 131.

[0034] Furthermore, the metal cylinders 1301 in the pair of third metal cylinder groups 133 are misaligned with the metal cylinders 1301 in the pair of first metal cylinder groups 131, that is, the metal cylinders 1301 in the third metal cylinder group 133 correspond to the gaps between the metal cylinders 1301 in the first metal cylinder group 131, or the metal cylinders 1301 in the first metal cylinder group 131 correspond to the gaps between the metal cylinders 1301 in the third metal cylinder group 133.

[0035] It is understandable that a pair of first metal pillar groups 131, a pair of second metal pillar groups 132, and a pair of third metal pillar groups 133 are equivalent to ideal metal surfaces to prevent energy leakage.

[0036] Generally speaking, the SIW structure is a microwave / millimeter-wave transmission structure that simulates a traditional rectangular waveguide by using a dielectric substrate (as a carrier for electromagnetic wave propagation), upper and lower metal layers (such as radiating plate 1 and circuit board module 2) and an array of metallized vias on both sides (such as a first metal column group 131, a second metal column group 132 and a third metal column group 133 formed by arranging metal cylinders 1301).

[0037] Specifically, the antenna element 12 is a slot structure that penetrates the radiating plate 1.

[0038] It should be noted that the signal of the waveguide antenna 100 is fed in from the antenna chip port (the antenna chip port can be set on the circuit board module or in a separate location) and transmitted to the antenna element 12 through the SIW structure.

[0039] Understandably, antenna element 12 can couple out electromagnetic energy confined inside the waveguide and radiate it into free space to form an electromagnetic beam that can be used for communication or detection.

[0040] In this embodiment, two antenna beam adjustment units 11 are symmetrically arranged about the axis of symmetry 1001, and multiple antenna units 12 are staggered between the two antenna beam adjustment units 11.

[0041] In this context, any one of the antenna beam adjustment units 11 has a preset first spacing d1 between its first center line 111 and its axis of symmetry 1001, and the first spacing d1 is one-quarter of the waveguide wavelength formed by the waveguide antenna 100 at the center frequency point of its operating frequency band.

[0042] In addition, there is a preset second spacing d2 between the second center lines 121 of two adjacent antenna elements 12, and the second spacing d2 is about half of the waveguide wavelength formed by the waveguide antenna 100 at the center frequency point of its operating frequency band. In fact, the second spacing d2 is slightly smaller than half of the waveguide wavelength formed by the waveguide antenna 100 at the center frequency point of its operating frequency band. This second spacing d2 is used to adjust the phase of the antenna element, adjust the side lobes of the waveguide antenna, and adjust the beam pointing of the waveguide antenna.

[0043] Furthermore, the substrate integrated waveguide structure 13 has a pair of first metal pillar groups 131, and the third center lines 1311 of the pair of first metal pillar groups 131 have a preset third spacing. .

[0044] Specifically, the fourth center line 122 of the multiple antenna elements 12 has a different fourth spacing d3 with respect to the axis of symmetry 1001, and the fourth spacing d3 is within the third spacing. Within a range of 10% to 20%, this fourth spacing d3 is used to adjust the electromagnetic field amplitude of each antenna element 12 to achieve amplitude weighting, and the waveguide antenna 100 further suppresses the sidelobe level of the waveguide antenna 100 by controlling the amplitude distribution.

[0045] Generally speaking, when the fourth spacing d3 is within the third spacing When adjusting between 0% and 25%, the greater the fourth spacing d3, the larger the amplitude of the waveguide antenna 100, and the fourth spacing d3 is the third spacing. The amplitude of waveguide antenna 100 reaches its maximum value when it is 25% of its maximum value.

[0046] To further explain, the antenna matching section 14 is a three-section matching section. The physical width of the antenna matching section 14 is one-quarter of the waveguide wavelength formed by the waveguide antenna 100 at the center frequency of its operating frequency band. This three-section matching section design can extend the bandwidth of the waveguide antenna 100.

[0047] The three-section matching segment refers to a multi-stage impedance matching technique used in antenna matching segment design. Its core purpose is to achieve impedance matching between the antenna chip port and the antenna element 12 over a wider frequency range through three transmission line segments of specific lengths, thereby significantly extending the operating bandwidth of the waveguide antenna 100.

[0048] In a waveguide or transmission line system, when a signal is transmitted from the antenna chip port to the antenna element 12, if the impedances of the two are mismatched, some signal energy will be reflected back, resulting in a decrease in efficiency. The antenna matching section 14 is one or more transmission lines inserted between the antenna chip port and the antenna element 12. Its function is like an impedance transformer, which can cancel the effect of impedance mismatch and allow the signal energy to be transmitted to the antenna element 12 to the maximum extent.

[0049] The three matching sections are equivalent to performing three consecutive, progressive impedance transformations. The three matching sections decompose the large total impedance transformation into three smaller, consecutive transformation steps, with each section responsible for a part of the impedance transformation, ultimately smoothly transitioning the antenna chip port impedance to the antenna element impedance.

[0050] The three-section matching section, through a multi-stage design, can maintain good impedance matching over a wide frequency range (e.g., 75GHz to 82GHz).

[0051] In summary, the use of a three-section matching section in the antenna matching section 14 enables the waveguide antenna 100 to operate efficiently throughout the entire operating frequency band with low reflection loss, thereby achieving broadband high-performance performance.

[0052] It should be noted that the axis of symmetry 1001 is parallel to the length direction of the antenna beam adjustment unit 11, the first center line 111, the third center line 1311 and the fourth center line 122 are parallel to the axis of symmetry 1001, and the second center line 121 is perpendicular to the axis of symmetry 1001.

[0053] In this embodiment of the application, the waveguide antenna 100 operates in the frequency band of 75 GHz to 82 GHz, and the center frequency of the waveguide antenna 100 is 78.5 GHz.

[0054] In some embodiments, such as Figure 5 and Figure 7 As shown, the radiating plate 1 is also provided with a positioning boss 15, and the positioning boss 15, the substrate integrated waveguide structure 13 and the antenna matching section 14 are located on the same side surface of the radiating plate 1.

[0055] In some embodiments, such as Figure 1 , Figure 2 and Figure 5 As shown, the waveguide antenna 100 also includes: a circuit board module 2 and a metal fastener 3.

[0056] It is understandable that the circuit board module 2 is attached to the positioning boss 15, and the circuit board module 2 is connected to the positioning boss 15 by metal fasteners 3. This allows the radiating plate 1 and the circuit board module 2 to be fastened by threads with metal fasteners 3 (such as screws) instead of traditional welding fixation. This enables the waveguide antenna 100 to achieve high performance while simplifying the manufacturing process and reducing production costs.

[0057] In some embodiments, such as Figure 2 , Figure 4 , Figure 7 , Figure 8 and Figure 9 As shown, the substrate integrated waveguide structure 13 has a pair of second metal pillar groups 132, and the fifth center line of the second metal pillar group 132 is perpendicular to the axis of symmetry 1001.

[0058] Specifically, a pair of first metal pillar groups 131 and a pair of second metal pillar groups 132 enclose a waveguide cavity 1302, an antenna matching section 14 is disposed in the waveguide cavity 1302, and an antenna element 12 passes through the radiating plate 1 and is connected to the waveguide cavity 1302.

[0059] In some embodiments, such as Figures 2-9 As shown, each first metal column group 131 is composed of M metal cylinders 1301 arranged along the length direction of the antenna beam adjustment unit 11 at a preset fifth spacing d.

[0060] Each second metal column group 132 is composed of N metal cylinders 1301 arranged along the width direction of the antenna beam adjustment unit 11 at a preset fifth spacing d.

[0061] In addition, each metal cylinder 1301 has a preset radius dimension, and M is greater than N.

[0062] In some embodiments, such as Figures 2-9 As shown, to prevent energy leakage, the SIW structure needs to meet the following conditions:

[0063] Specifically, the substrate integrated waveguide structure 13 (SIW) has its own operating frequency and the radius of the metal cylinder. d represents the waveguide wavelength of the substrate integrated waveguide structure 13, and d represents the fifth spacing. This is the cutoff wavelength of the substrate integrated waveguide structure.

[0064] In some embodiments, such as Figures 2-9 As shown, and The calculation formula is as follows:

[0065] In this embodiment of the application, 'a' represents the third spacing. For the free space wavelength of the substrate integrated waveguide structure 13, is the relative permittivity of the dielectric substrate of the substrate integrated waveguide structure 13.

[0066] In some embodiments, such as Figures 2-9 As shown, and The calculation formula is as follows:

[0067] It should be noted that, The cutoff wavelength of waveguide antenna 100 is... The waveguide wavelength of waveguide antenna 100 is... λ is the free space wavelength of waveguide antenna 100.

[0068] In some embodiments, such as Figures 1-9 As shown, the physical width of each antenna element 12 is 0.6 mm to 1.5 mm.

[0069] It is understandable that the physical length of each antenna element 12 is half the free space wavelength formed by the waveguide antenna 100 at the center frequency of its operating frequency band. This allows the antenna element 12 to be in a resonant state, at which point its radiation resistance is at its maximum and its radiation efficiency is at its highest, thus ensuring that the waveguide antenna 100 can work effectively in the operating frequency band from 75 GHz to 82 GHz.

[0070] In some embodiments, such as Figures 1-9 As shown, the physical width of the antenna beam adjustment unit 11 is 0.6 mm to 1.5 mm.

[0071] To help readers understand the concept of this invention, a simulation experiment of the waveguide antenna 100 is presented below.

[0072] Simulation results of waveguide antenna return loss are as follows: Figure 10 As shown, from Figure 10 As can be directly seen from the simulation results, the return loss S11 of the waveguide antenna 100 is less than -11dB throughout the entire operating frequency band (75GHz to 82GHz). This indicates that the input impedance of the waveguide antenna 100 is well matched with the feed port, thereby ensuring that the signal energy fed from the antenna chip port can be effectively radiated out instead of being reflected back, thus enabling the waveguide antenna 100 to work stably in a frequency band up to 7GHz.

[0073] The simulation results of waveguide antenna gain are as follows Figure 11 As shown, from Figure 11 As can be directly seen from the simulation results, the simulated waveguide antenna gain Gain is greater than 14.9 dBi and less than 15.6 dBi throughout the entire operating frequency band (75 GHz to 82 GHz).

[0074] Simulation results of waveguide antenna at 75 GHz frequency PHi=0° section are as follows: Figure 12 As shown, the waveguide antenna 100 has a horizontal beamwidth of 35.6°, a main lobe amplitude of 14.9 dBi, a main lobe direction of 1°, and a sidelobe level of less than -20.4 dB at a working frequency of 75 GHz.

[0075] Simulation results of waveguide antenna at 75 GHz frequency with a PHi=90° cross section are as follows: Figure 13 As shown, the waveguide antenna 100 has a vertical beamwidth of 21.3°, a main lobe amplitude of 14.9 dBi, a main lobe direction of 1°, and a sidelobe level of less than -16.8 dB at a working frequency of 75 GHz.

[0076] Simulation results of waveguide antenna at 78.5 GHz frequency PHi=0° section are as follows: Figure 14As shown, the waveguide antenna 100 has a horizontal beamwidth of 34.2°, a main lobe amplitude of 15.6 dBi, a main lobe direction of 0°, and a sidelobe level of less than -21.7 dB at an operating frequency of 78.5 GHz.

[0077] Simulation results of a waveguide antenna with a 78.5 GHz frequency point PHi=90° cross section are as follows: Figure 15 As shown, the waveguide antenna 100 has a vertical beamwidth of 20.2°, a main lobe amplitude of 15.6 dBi, a main lobe direction of 1°, and a sidelobe level of less than -15.9 dB at an operating frequency of 78.5 GHz.

[0078] Simulation results of waveguide antenna at 82G frequency PHi=0° section are as follows: Figure 16 As shown, the waveguide antenna 100 has a horizontal beamwidth of 33.5°, a main lobe amplitude of 15.4 dBi, a main lobe direction of 1°, and a sidelobe level of less than -22.4 dB at an operating frequency of 82 GHz.

[0079] Simulation results of waveguide antenna at 82 GHz frequency PHi=90° section are as follows: Figure 17 As shown, the waveguide antenna 100 has a vertical beamwidth of 19.6°, a main lobe amplitude of 15.6 dBi, a main lobe direction of 2°, and a sidelobe level of less than -14.6 dB at an operating frequency of 82 GHz.

[0080] like Figures 11-17 As shown, the gain of waveguide antenna 100 fluctuates between 14.9 dBi and 15.6 dBi across the entire operating frequency band (75 GHz to 82 GHz), with a fluctuation of only 0.7 dBi. This indicates that the gain stability of waveguide antenna 100 is good across the entire operating frequency band (75 GHz to 82 GHz), thus enabling waveguide antenna 100 to have good bandwidth stability across the entire operating frequency band (75 GHz to 82 GHz).

[0081] Reference Figures 12-17 It can be seen that the horizontal beamwidth (Phi=0°) of the entire operating frequency band (75GHz to 82GHz) smoothly transitions from 35.6° to 33.5°, and the vertical beamwidth (Phi=90°) of the entire operating frequency band (75GHz to 82GHz) converges from 21.3° to 19.6°. This indicates that the beamwidth changes smoothly and regularly, thus showing that the radiation direction of the waveguide antenna 100 maintains a high degree of consistency and predictability throughout the entire operating frequency band (75GHz to 82GHz), without any obvious beam distortion.

[0082] Combination Figures 12-17It can be seen that the horizontal beamwidth and the vertical beamwidth are different, which means that the beam of the waveguide antenna 100 is a symmetrical but non-circular ellipse, thus enabling the waveguide antenna 100 to become a high-gain directional antenna.

[0083] Please refer to Figures 12-17 The main lobe direction is very stable throughout the entire operating frequency band (75GHz to 82GHz), with a maximum offset of only 2° (Phi=90° section at 82GHz). This indicates that the beam pointing of the waveguide antenna 100 is not sensitive to frequency changes, further enhancing the reliability of the waveguide antenna 100 in the 7 GHz wideband.

[0084] like Figures 12-17 As shown, the sidelobe level is less than -14.6 dB throughout the entire operating frequency band (75 GHz to 82 GHz), with the best performance reaching -22.4 dB (82 GHz, Phi=0° section). This indicates that the waveguide antenna 100 has excellent low sidelobe characteristics. Low sidelobe means that the energy of the waveguide antenna 100 is highly concentrated in the direction of the main beam. This can effectively reduce interference from other directions, thereby improving the anti-interference capability of the waveguide antenna 100 and the signal-to-noise ratio of communication.

[0085] In this embodiment, although the performance is optimal at an operating frequency of 78.5 GHz, the performance degradation at other frequencies is very minor. For example, at an operating frequency of 82 GHz at the edge of the band, the waveguide antenna 100 still achieves a gain of 15.4 dBi and excellent sidelobe suppression (-22.4 dB), demonstrating that the waveguide antenna 100 has high performance across the entire operating frequency band (75 GHz to 82 GHz), rather than just at the center frequency.

[0086] In summary, the waveguide antenna 100 simultaneously achieves high gain, low sidelobes, and stable beam shape and directionality across the entire operating frequency band from 75 GHz to 82 GHz. Such performance indicators fully meet the requirements of missile-borne, airborne, and shipborne search and tracking antennas for high gain and low sidelobes. Therefore, the technical solution of the waveguide antenna 100 can achieve broadband high-performance performance requirements.

[0087] In summary, the waveguide antenna provided in this embodiment of the invention has a preset second spacing between the second center lines of two adjacent antenna elements. This second spacing is half the waveguide wavelength formed by the waveguide antenna at the center frequency of its operating frequency band. This second spacing is used to adjust the phase of the antenna elements, the sidelobes of the waveguide antenna, and the beam pointing of the waveguide antenna. The substrate integrated waveguide structure in this waveguide antenna has a pair of first metal pillar groups, and there is a third spacing between the third center lines of the pair of first metal pillar groups. The fourth center lines of multiple antenna elements in this waveguide antenna have different fourth spacings with respect to the axis of symmetry, and the fourth spacing is in the range of 10% to 20% of the third spacing. This fourth spacing is used to adjust the amplitude of the antenna elements. The antenna matching section in this waveguide antenna is a three-section matching section, and the physical width of the antenna matching section is one-quarter of the waveguide wavelength formed by the waveguide antenna at the center frequency of its operating frequency band. This three-section matching section design can extend the bandwidth of this waveguide antenna. In conclusion, the technical solution of this waveguide antenna can achieve the requirements of broadband high-performance indicators.

[0088] The above description, in conjunction with specific / preferred embodiments, provides a further detailed explanation of the present invention, but it should not be construed as limiting the specific implementation of the invention to these descriptions. Those skilled in the art will recognize that various modifications and improvements can be made without departing from the concept of the present invention, and all such modifications and improvements fall within the scope of protection of the present invention.

Claims

1. A waveguide antenna, characterized in that, At least including: The radiating plate is provided with two antenna beam adjustment units, multiple antenna units, a substrate integrated waveguide structure, and an antenna matching section; The two antenna beam adjustment units are symmetrically arranged about the axis of symmetry, and the plurality of antenna units are staggered between the two antenna beam adjustment units; The first centerline of any one of the antenna beam adjustment units has a preset first distance from the axis of symmetry, and the first distance is one-quarter of the waveguide wavelength formed by the waveguide antenna at the center frequency point of its operating frequency band. There is a preset second spacing between the second center lines of two adjacent antenna elements, and the second spacing is half of the waveguide wavelength formed by the waveguide antenna at the center frequency point of its operating frequency band; The substrate integrated waveguide structure has a pair of first metal pillar groups, and there is a preset third spacing between the third center lines of the pair of first metal pillar groups; The fourth center lines of the plurality of antenna elements have different fourth spacings with respect to the axis of symmetry, and the fourth spacings are in the range of 10% to 20% of the third spacing; The antenna matching section is a three-section matching section, and the physical width of the antenna matching section is one-quarter of the waveguide wavelength formed by the waveguide antenna at the center frequency point of its operating frequency band. Wherein, the axis of symmetry is parallel to the length direction of the antenna beam adjustment unit, the first center line, the third center line and the fourth center line are parallel to the axis of symmetry, and the second center line is perpendicular to the axis of symmetry.

2. The waveguide antenna according to claim 1, characterized in that, The radiating plate is also provided with a positioning boss, and the positioning boss, the substrate integrated waveguide structure and the antenna matching section are located on the same side surface of the radiating plate.

3. The waveguide antenna according to claim 2, characterized in that, Also includes: The circuit board module and the metal fastener are provided, wherein the circuit board module is fitted to the positioning boss and the circuit board module is connected to the positioning boss by the metal fastener.

4. The waveguide antenna according to claim 1, characterized in that, The substrate integrated waveguide structure has a pair of second metal pillar groups, and the fifth center line of the second metal pillar groups is perpendicular to the axis of symmetry; A pair of first metal pillars and a pair of second metal pillars enclose a waveguide cavity, the antenna matching section is disposed in the waveguide cavity, and the antenna element passes through the radiating plate and is connected to the waveguide cavity.

5. The waveguide antenna according to claim 4, characterized in that, Each of the first metal pillar groups consists of M metal cylinders arranged along the length direction of the antenna beam adjustment unit at a preset fifth spacing; Each of the second metal pillar groups consists of N metal cylinders arranged along the width direction of the antenna beam adjustment unit at a preset fifth spacing; Each of the metal cylinders has a preset radius, and M is greater than N.

6. The waveguide antenna according to claim 5, characterized in that, Where r is the radius of the metal cylinder. d is the waveguide wavelength of the substrate integrated waveguide structure, and d is the fifth spacing. The cutoff wavelength is the wavelength of the substrate integrated waveguide structure.

7. The waveguide antenna according to claim 6, characterized in that, Where a is the third spacing. The free-space wavelength of the substrate-integrated waveguide structure is given. is the relative permittivity of the dielectric substrate of the substrate integrated waveguide structure.

8. The waveguide antenna according to claim 7, characterized in that, in, The cutoff wavelength of the waveguide antenna is [wavelength value missing]. The waveguide wavelength of the waveguide antenna is given. λ is the free space wavelength of the waveguide antenna.

9. The waveguide antenna according to any one of claims 1-8, characterized in that, The physical width of each antenna element is 0.6 mm to 1.5 mm; The physical length of each antenna element is half the free space wavelength formed by the waveguide antenna at the center frequency of its operating frequency band.

10. The waveguide antenna according to any one of claims 1-8, characterized in that, The physical width of the antenna beam adjustment unit is 0.6 mm to 1.5 mm.

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