Miniaturized waveguide antenna device and method for twisting electric field

Abstract

The invention discloses a miniaturized waveguide antenna device and a method for twisting an electric field, and belongs to the technical field of radar antennae, the miniaturized waveguide antenna device comprises an antenna device, and the antenna device comprises a guided wave transmission line, a waveguide port, a first antenna element, a second antenna element, a power wave division element, an electric field twisting element and a frame. By means of the mode, the waveguide antenna device is innovatively provided by combining the performance advantages of the waveguide antenna and considering manufacturing problems such as machining tolerance, complex antenna structure design is avoided, and miniaturization, low-profile and high-performance radars, especially automobile radars, can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of radar antennas, and in particular to a miniaturized waveguide antenna device and a method for twisting an electric field. Background Art

[0002] The signal-to-noise ratio of the radar received signal determines the radar system's observation accuracy and detection range. According to the classic radar equation, one of the key components, the radar antenna, is particularly critical and is the direction of efforts to improve radar performance. The mainstream antenna technology currently used in millimeter-wave automotive radars is based on PCB printed antennas. In order to improve antenna radiation and reduce transmission loss, a low-loss high-frequency dielectric substrate suitable for millimeter-wave applications is used under the antenna.

[0003] For example, Chinese patent CN106981710B discloses a waveguide device, an antenna device, and a radar that suppress the reflection of electromagnetic waves in the curved portion of a waveguide component. The waveguide device comprises: a conductive component having a conductive surface; a waveguide component having a conductive waveguide surface that is opposite to the conductive surface and is in a strip shape and extends along the conductive surface; and an artificial magnetic conductor located on both sides of the waveguide component. The waveguide component has a curved portion that changes the direction of extension. The waveguide defined by the conductive surface, the waveguide surface, and the artificial magnetic conductor includes a gap expansion portion in which the gap between the conductive surface and the waveguide surface is partially expanded. When viewed from a direction perpendicular to the conductive surface, at least a portion of the curved portion overlaps with the gap expansion portion.

[0004] However, the technology has the following problems: the antenna device is based on a PCB printed antenna, which does not take into account the high raw material cost of the high-frequency substrate, increases the manufacturing cost such as the processing flow, and has high requirements for processing accuracy.

[0005] Based on this, the present invention designs a miniaturized waveguide antenna device and a method for twisting the electric field to solve the above problems. Summary of the invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides a miniaturized waveguide antenna device and a method for twisting an electric field.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] A miniaturized waveguide antenna device, comprising an antenna device, wherein the antenna device comprises a waveguide transmission line, a waveguide port, an antenna element 1, an antenna element 2, a power wave splitting element, an electric field twisting element and a frame;

[0009] A waveguide port is provided on the left side of the waveguide transmission line, the waveguide port is connected to the electronic system, and the waveguide port is used to transmit and receive signals sent by the electronic system;

[0010] The antenna element 1 and the antenna element 2 form an array combination in space, and the lower ends of the antenna element 1 and the antenna element 2 are connected to at least one waveguide transmission line;

[0011] The power splitter element is used to distribute power of a signal from an electronic system to achieve a focusing effect on the propagation signal in space. The power splitter element is connected to at least one antenna element 1 and antenna element 2. The antenna element 1 and antenna element 2 are combined into an antenna array.

[0012] The electric field twisting element is used to twist the polarization direction of the electric field entering the antenna element 1 and the antenna element 2 from the waveguide transmission line to meet the antenna polarization requirements in the radar system; there are multiple electric field twisting elements, and the antenna element 1 and the antenna element 2 are respectively connected to an electric field twisting element; that is, one antenna element is equipped with one electric field twisting element;

[0013] The geometrical axes of the antenna element 1 and the antenna element 2 are coaxial with the center of the electric field twisting element;

[0014] The center of the electric field twisting element is a bias center.

[0015] The waveguide transmission line, waveguide port, antenna element one, antenna element two, power wave splitting element, and electric field twisting element are all arranged inside the frame, and the frame is made of conductive metal, or a metallized injection molding material groove, or other conductive materials.

[0016] Furthermore, the cross-sectional structure of the waveguide transmission line is a rectangle or a rectangular ridge waveguide with a reduced cross-section. The cross-section of the waveguide transmission line is a closed pipe surrounded by wide walls and narrow walls, and its cross-section is a rectangle, the long side of the rectangle is the wide wall, and the short side is the narrow wall.

[0017] Furthermore, antenna element one and antenna element two are rectangular open waveguides or horn-shaped open waveguides, and the radiation port surface is rectangular. The upper ends of antenna element one and antenna element two are radiation ports, and the cross-sectional shape of the radiation port is rectangular. Antenna element one and antenna element two are both placed on the narrow wall of the waveguide transmission line, and the radiation port surfaces of antenna element one and antenna element two are parallel to the narrow wall.

[0018] Furthermore, the antenna element 1 and the antenna element 2 are coaxially arranged in the array, and the axis thereof is parallel to or orthogonal to the electric field polarization direction of the rectangular radiation aperture.

[0019] Furthermore, the antenna array includes a center-fed type, an edge-fed type, and a hybrid-fed type;

[0020] Center-fed type means 1 divided into N channels, the typical value of N is 4, or other even values. After power splitting, the signal is centrally symmetrical, with equal amplitude and phase, or unequal amplitude and unequal phase.

[0021] The edge-fed type is to connect M antenna elements in series, where the typical value of M is 4 or other integers.

[0022] The hybrid feeding type includes two directions, which are orthogonal to each other on the plane, that is, the power splitting mode in one direction is the center feeding type, and the power splitting mode in the other direction is the edge end feeding type.

[0023] Furthermore, there is a short-circuit point at the end of the waveguide transmission line, and the distance between the ends of the antenna element 1 and the antenna element 2 and the short-circuit point is 1 / 4 of the waveguide wavelength or an integral multiple thereof.

[0024] Furthermore, in a coaxial array orthogonal to the electric field polarization direction, the characteristics of the adjacently arranged antenna element 1 and antenna element 2 are:

[0025] 1. The phases of the waveguide transmission line and the power wave splitting element connected to the antenna element 1 and the antenna element 2 after wave splitting are the same. After the electric field twisting element with the same twisting direction is used, the electric field twisting direction is the same +90 degrees, or the same -90 degrees, resulting in the radiation polarization phases of the antenna element 1 and the antenna element 2 being the same phase;

[0026] 2. The internal phases of the waveguide transmission line and the power splitter element connected to antenna element 1 and antenna element 2 are opposite after wave splitting. After using electric field twisting elements with opposite twisting directions, one of the electric field twisting directions is +90 degrees and the other is -90 degrees, resulting in the radiation polarization phases of antenna element 1 and antenna element 2 being in phase.

[0027] Furthermore, in a coaxial array parallel to the electric field polarization direction, the characteristics of the adjacently arranged antenna element 1 and antenna element 2 are:

[0028] 1. After adopting electric field twisting elements with the same polarization direction and the same phase, the arrangement spacing of multiple antenna elements 1 is 1 waveguide wavelength or the arrangement spacing of multiple antenna elements 2 is 1 waveguide wavelength, so that the radiation polarization phase of antenna element 1 or antenna element 2 can be in phase;

[0029] Second, after using electric field twisting elements with the same twisting direction and opposite phases, the arrangement spacing of antenna element 1 and antenna element 2 is 1 / 2 times the waveguide wavelength, so that the radiation polarization phases of antenna element 1 and antenna element 2 are in phase.

[0030] Furthermore, the method for antenna element 1 and antenna element 2 to achieve the same polarization direction and opposite phase is:

[0031] 1. Deflected waveguide transmission line, with twist angles of +α and -α respectively;

[0032] 2. Rotate the rectangular waveguide with rotation angles of +α and -α respectively;

[0033] 3. A boss on the wide wall of the offset waveguide, wherein the boss is mirror-symmetrical about the coordinate plane where the second offset center is located.

[0034] In order to better achieve the purpose of the present invention, the present invention also provides a method for twisting the electric field of a miniaturized waveguide antenna device;

[0035] One of the methods is to deflect the waveguide transmission line: a deflected waveguide transmission line is generated on the axis of the waveguide transmission line, and the deflection angle is α, and α is not 0;

[0036] The second method is to rotate the rectangular waveguide: place an axially rotated rectangular waveguide on the axis of the waveguide transmission line, and the rotation angle is α, which is not 0;

[0037] The third method is to offset the boss on the wide wall of the waveguide: there is a rectangular boss with a width of W on the upper wide wall and the lower wide wall surface of the waveguide transmission line, and there is an offset O at the center position of the two.

[0038] Compared with the prior art, the present invention has the following beneficial effects: 1. The solution proposed by the present invention can realize a low-profile waveguide antenna device in the height dimension through the combination of an antenna, an electric field twisting element, and a waveguide transmission line, so as to facilitate the realization of a miniaturized radar sensor;

[0039] 2. The solution proposed by the present invention can realize an antenna device with high radiation efficiency;

[0040] 3. The solution proposed in the present invention can achieve stable antenna elevation beam pointing within a 76-81 GHz broadband;

[0041] 4. The solution proposed in the present invention can achieve a horizontal 3dB beam width of the antenna within the 76-81GHz broadband better than 120°. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] 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.

[0043] Figure 1A side top perspective view of a waveguide antenna device according to the present invention;

[0044] Figure 2 A top view of a method 200A for twisting a waveguide transmission line according to the present invention;

[0045] Figure 3 An isometric view of a method 200A for twisting a waveguide transmission line according to the present invention;

[0046] Figure 4 A top view of a method 200B using a rotating rectangular waveguide according to the present invention;

[0047] Figure 5 An isometric view of a method 200B using a rotated rectangular waveguide according to the present invention;

[0048] Figure 6 A top view of a method 200C using an offset waveguide wide-wall boss according to the present invention;

[0049] Figure 7 An isometric view of a method 200C using an offset waveguide wide-wall boss according to the present invention;

[0050] Figure 8 A top view of a first embodiment of an adjacent antenna array according to the present invention;

[0051] Fig. 9 A top view of a second embodiment of an adjacent antenna array according to the present invention;

[0052] Fig.10 An array topology diagram of a first antenna array variant of a waveguide antenna device according to the present invention;

[0053] Fig.11 An isometric view of a first antenna array variant according to the present invention in which a waveguide antenna is transposed;

[0054] Fig.12 An array topology diagram of a second antenna array variant of a waveguide antenna device according to the present invention;

[0055] Fig.13 An isometric view of a second antenna array variant of a waveguide antenna device according to the present invention;

[0056] Fig.14 An array topology diagram of a third antenna array variant of a waveguide antenna device according to the present invention;

[0057] Fig.15 An isometric view of a third antenna array variant of a waveguide antenna device according to the present invention;

[0058] Fig.16 An array topology diagram of a fourth antenna array variant of a waveguide antenna device according to the present invention;

[0059] Fig.17 An isometric view of a fourth antenna array variant of a waveguide antenna device according to the present invention;

[0060] Fig.18 An array topology diagram of a fifth antenna array variant of a waveguide antenna device according to the present invention;

[0061] Fig.19 An isometric view of a fifth antenna array variant of a waveguide antenna device according to the present invention;

[0062] Fig. 20 A return loss curve diagram of an embodiment of a waveguide antenna device according to the present invention;

[0063] Fig.21 The figure is a curve diagram of the azimuth antenna pattern in the 76-81 GHz frequency band of an embodiment of the waveguide antenna device proposed in the present invention.

[0064] The numbers in the figure represent:

[0065] 1. Antenna device; 100. Waveguide transmission line; 102. Waveguide port; 101A. Antenna element one; 101B. Antenna element two; 103. Power splitter element; 104. Electric field torsion element; 105. Frame; 202A. Deflected waveguide transmission line; 204A. Terminal short-circuit point one; 206A. Offset center one; 202B. Rectangular waveguide; 204B. Terminal short-circuit point two; 206B. Offset center two; 202C. Boss; 204C. Terminal short-circuit point three; 206C. Offset center three; 301A. Electric field polarization direction one; 301B. Electric field polarization direction two; 401A. Output phase one; 403. Concave one; 404. Concave two; 405. Concave three; 406. Concave four; 401B. Output phase two. DETAILED DESCRIPTION

[0066] 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.

[0067] For the convenience of explanation, the coordinate system is defined as follows:

[0068] xoz is the azimuth plane, the elevation angle is 0 degrees, and the antenna polarization direction is horizontal polarization on this plane;

[0069] yoz is the elevation plane, the azimuth angle is 0 degrees, and the antenna polarization direction is vertical polarization on this plane.

[0070] Embodiment 1: In some embodiments, please refer to the drawings of the specification Figure 1 A miniaturized waveguide antenna device comprises an antenna device 1, wherein the antenna device 1 comprises a waveguide transmission line 100, a waveguide port 102, an antenna element 1 101A, an antenna element 2 101B, a power splitter element 103, an electric field twisting element 104 and a frame 105;

[0071] A waveguide port 102 is provided on the left side of the waveguide transmission line 100, and the waveguide port 102 is connected to the electronic system, and the waveguide port 102 is used to transmit and receive signals sent by the electronic system;

[0072] The antenna element 1 101A and the antenna element 2 101B form an array combination in space, and the lower ends of the antenna element 101A and the antenna element 2 101B are connected to at least one waveguide transmission line 100;

[0073] The power splitter element 103 is used to distribute power of the signal from the electronic system to achieve the focusing effect of the propagation signal in space. The power splitter element 103 is connected to at least one antenna element 101A and antenna element 2 101B. The antenna element 101A and antenna element 2 101B are combined into an antenna array.

[0074] The electric field twisting element 104 is used to twist the polarization direction of the electric field entering the antenna element 101A and the antenna element 101B from the waveguide transmission line 100 to meet the antenna polarization requirements in the radar system; there are multiple electric field twisting elements 104, and the antenna element 101A and the antenna element 101B are respectively connected to an electric field twisting element 104; that is, one antenna element is equipped with one electric field twisting element 104;

[0075] The purpose of twisting the electric field twisting element 104 is to twist the electric field polarized in the vertical plane direction in the waveguide transmission line 100 into a horizontal direction, so as to meet the requirements of the radar system for the antenna to achieve horizontal polarization.

[0076] The geometric axes of the antenna element 1 101A and the antenna element 2 101B are coaxial with the center of the electric field twisting element 104;

[0077] The center of the electric field twisting element 104 is an offset center.

[0078] The waveguide transmission line 100, waveguide port 102, antenna element 1 101A, antenna element 2 101B, power wave splitting element 103, and electric field twisting element 104 are all arranged inside a frame 105, and the frame 105 is made of a conductive metal, or a metallized injection molding material groove, or other conductive materials;

[0079] The waveguide transmission line 100, waveguide port 102, antenna element 1 101A, antenna element 2 101B, power splitter element 103, electric field torsion element 104 and frame 105 together constitute a low-profile waveguide antenna device, which is convenient for realizing a miniaturized radar sensor.

[0080] The waveguide transmission line 100 has a typical structure of a rectangle or a rectangular ridge waveguide with a reduced cross section; the cross section of the waveguide transmission line 100 is a closed pipe surrounded by wide walls and narrow walls; its cross section is a rectangle, the long side of the rectangle is the wide wall, and the short side is the narrow wall.

[0081] The waveguide transmission line 100 and the power splitter element 103 both include narrow walls and wide walls. The dimensions may be WR-12 (3.0 mm long, 1.5 mm wide), WR-10 (2.54 mm long, 1.27 mm wide), or other reasonable dimensions determined according to the antenna operating frequency band.

[0082] Due to the different directions of electric field twisting, the electric field twisting element 104 is divided into two categories, A and B. Compared with category A, category B will cause the polarization direction of the antenna element to be the same, but the phase forms pi (phase value), that is, the difference of anti-phase. Arranged in a colinear manner in the y-axis direction of the antenna array, the antenna element 1 101A and the antenna element 2 101B are determined by the different twisting directions of the electric field twisting element 104;

[0083] The antenna element 1 101A and the antenna element 2 101B are integrally placed on the narrow wall of the waveguide transmission line 100 .

[0084] Antenna element 1 101A and antenna element 2 101B are both rectangular open waveguides or horn-shaped open waveguides. The upper ends of antenna element 101A and antenna element 2 101B are radiation ports, and the cross-sectional shape of the radiation ports is rectangular. Antenna element 1 101A and antenna element 2 101B are both placed on the narrow wall of the waveguide transmission line 100, and the radiation port surfaces of antenna element 1 101A and antenna element 2 101B are both parallel to the narrow wall.

[0085] The antenna element 1 101A and the antenna element 2 101B are coaxially arranged in the array, and the axis thereof is parallel to or orthogonal to the electric field polarization direction of the rectangular radiation aperture.

[0086] The antenna array includes a center-fed type, an edge-fed type, and a hybrid-fed type;

[0087] Center-fed type means 1 divided into N channels, the typical value of N is 4, or other even values. After power splitting, the signal is centrally symmetrical, with equal amplitude and phase, or unequal amplitude and unequal phase.

[0088] The edge-fed type is to connect M antenna elements in series, where the typical value of M is 4 or other integers.

[0089] The hybrid feeding type includes two directions, which are orthogonal to each other on the plane, that is, the power splitting mode in one direction is the center feeding type, and the power splitting mode in the other direction is the edge end feeding type.

[0090] There is a short-circuit point at the end of the waveguide transmission line 100, and the distance between the ends of the antenna element 1 101A and the antenna element 2 101B and the short-circuit point is 1 / 4 of the waveguide wavelength or an integral multiple thereof.

[0091] In a coaxial array orthogonal to the electric field polarization direction, the characteristics of the adjacently arranged antenna element 101A and antenna element 2 101B are:

[0092] 1. The internal phases of the waveguide transmission line 100 and the power wave splitting element 103 connected to the antenna element 101A and the antenna element 101B are the same after wave splitting. After the electric field twisting element with the same twisting direction is used, the electric field twisting direction is the same +90 degrees, or the same -90 degrees, resulting in the effect that the radiation polarization phases of the antenna element 101A and the antenna element 101B are the same phase;

[0093] 2. The internal phases of the waveguide transmission line 100 and the power splitter element 103 connected to the antenna element 101A and the antenna element 101B are opposite after splitting. After using electric field twisting elements with opposite twisting directions, one of the electric field twisting directions is +90 degrees and the other is -90 degrees, resulting in the radiation polarization phases of the antenna element 101A and the antenna element 101B being in phase.

[0094] In a coaxial array parallel to the electric field polarization direction, the characteristics of the adjacently arranged antenna element 1 101A and antenna element 2 101B are:

[0095] 1. After adopting the electric field twisting element 104 with the same polarization direction and the same phase, the arrangement spacing of the plurality of antenna elements 101A is 1 waveguide wavelength or the arrangement spacing of the plurality of antenna elements 2 101B is 1 waveguide wavelength, so that the radiation polarization phase of the antenna element 1 101A or the antenna element 2 101B is in phase;

[0096] Second, after using electric field twisting elements with the same twisting direction and opposite phases, the arrangement spacing of antenna element 101A and antenna element 2 101B is 1 / 2 times the waveguide wavelength, so that the radiation polarization phases of antenna element 101A and antenna element 2 101B are in phase.

[0097] In terms of signal transmission, when the antenna device 1 is in the transmitting mode, the waveguide port 102 obtains the signal from the electronic system, and then transmits it in the waveguide transmission line 100, and then passes through the power splitter element 103 to split the single path into 4 branch signals. Each branch has a waveguide transmission line 100 that is transitionally connected to the power splitter element 103 through the electric field twisting element 104. Finally, the antenna element 1 101A and the antenna element 2 101B twist the polarization direction of the electric field and radiate the signal into the air. This transmission process is that the antenna device 1 transmits signals as a transmitting antenna.

[0098] When the antenna device 1 is in the receiving mode, the signal transmission process is the reverse process of the above process, for example, the power splitter element 103 combines the signals on the branch into a single path, and then continues to transmit to the waveguide port 102. The transmission phase of the branch output of the 1-to-4-way power splitter element 103 is within the working frequency band (pi, 0, 0, pi), and the selected electric field twisting element 104 combination sequence is BAAB, and the interconnected antenna element 101B, antenna element 1 101A, antenna element 1 101A, and antenna element 2 101B have a phase of (0, 0, 0, 0), that is, in phase, and the antenna device achieves high radiation efficiency.

[0099] Embodiment 2: In some embodiments, Figure 2 and Figure 3 As shown, as a preferred embodiment of the present invention, the electric field twisting element 104 adopts a method 200A of twisting a waveguide transmission line: using a deflected waveguide transmission line 202A and an end short-circuit point 204A;

[0100] The antenna element 1 101A and the antenna element 2 101B are combined into an antenna array 101;

[0101] One end of the waveguide transmission line 100 is connected to the deflected waveguide transmission line 202A, and the antenna array 101 is connected to the combination of the deflected waveguide transmission line 202A and the waveguide transmission line 100;

[0102] The method for the antenna array 101 to achieve the same polarization direction and opposite phase is to deflect the waveguide transmission line 202A, and the twist angles are +α and -α respectively.

[0103] In this embodiment, the waveguide transmission line 100 extends on the x-axis, and the internal electric field polarization direction is on the y-axis. A deflection of an angle α is generated at the deflection waveguide transmission line 202A, resulting in a rotation of the electric field polarization direction in the xoy plane.

[0104] After the deflected electric field enters the antenna array 101, due to the polarization suppression effect, only the electric field component in the x-axis direction is retained, and the radiation signal is horizontally polarized. The antenna array 101 is an open waveguide antenna, which is vertically placed on the narrow wall of the waveguide transmission line 100 and has a certain depth H of embedding to control the energy coupling strength entering the antenna element 101A and the antenna element 2 101B.

[0105] The geometric center of the electric field twisting element 104 in the xoy plane coincides with the offset center 206A of the deflected waveguide transmission line 202A in projection.

[0106] From the top view, the antenna center of the antenna array 101 and the offset center 206A are coincident, and the end short-circuit point 204A of the waveguide transmission line 100 is spaced from the offset center 206A by 1 / 4 waveguide wavelength or an integer multiple thereof.

[0107] Embodiment 3: In some embodiments, Figure 4-Figure 5 As shown, as a preferred embodiment of the present invention, the electric field twisting element 104 adopts a method 200B of rotating a rectangular waveguide: a rectangular waveguide 202B is adopted;

[0108] The antenna element 1 101A and the antenna element 2 101B are combined into an antenna array 101;

[0109] One end of the waveguide transmission line 100 is connected to a port of the rectangular waveguide 202B, and the antenna array 101 is connected to one end of the rectangular waveguide 202B.

[0110] The method for the antenna array 101 to achieve the same polarization direction and opposite phase is to rotate the rectangular waveguide 200B, and the rotation angles are +α and -α respectively;

[0111] In this embodiment, the waveguide transmission line 100 extends on the x-axis, and the polarization direction of the electric field inside is on the y-axis.

[0112] At the second short-circuit point 204B at the end of the waveguide transmission line 100, a rectangular waveguide 202B with a rotation angle of α is placed at a position that is 1 / 4 of the waveguide wavelength or an integer multiple thereof from the second short-circuit point 204B at the end. The length and width of the waveguide may be different from the cross-sectional dimensions of the waveguide transmission line 100. The height H is the embedding depth, which controls the energy coupling intensity entering the antenna array 101. The antenna array 101 is a horn-shaped open waveguide antenna, which is placed vertically on the narrow wall of the waveguide transmission line 100;

[0113] The geometric center of the electric field twisting element 104 on the xoy plane coincides with the rotation center 206B in projection.

[0114] Embodiment 4: In some embodiments, Figure 6-Figure 7 As shown, as a preferred embodiment of the present invention, the electric field twisting element 104 adopts a method 200C of offsetting the waveguide wide wall boss: using a boss 202C;

[0115] Antenna element one 101A and antenna element two 101B are combined into antenna array 101; one side of the waveguide transmission line 100 is connected to the boss 202C, and the antenna array 101 is connected to the waveguide transmission line 100 and the boss 202C combination; the method for the antenna array 101 to achieve the same polarization direction and opposite phase is to offset the boss 202C on the wide wall of the waveguide, and the boss 202C is mirror-symmetric about the coordinate plane where the offset center two 206C is located.

[0116] In this embodiment, the waveguide transmission line 100 extends on the x-axis, and the polarization direction of the electric field inside is on the y-axis.

[0117] At the end short-circuit point three 204C of the waveguide transmission line 100, an open waveform antenna array 101 is placed at a position where the distance from the end short-circuit point three 204C is 1 / 4 of the waveguide wavelength or an integer multiple thereof.

[0118] At the diagonal position below the antenna array 101, a boss 202C is fixedly connected to the wide wall of the waveguide transmission line 100 to achieve disturbance of the polarization direction of the internal electric field.

[0119] The offset distance of the two bosses 202C on the x-axis is O, the width is W, and the depth is H. The offset center 206C coincides with the projection of the geometric center of the antenna array 101 on the xoy plane.

[0120] Compared with the third embodiment and the second embodiment, this embodiment can achieve the same antenna radiation characteristic effect while being compact in size because the projection area on xoy is small.

[0121] Embodiment 5: In some embodiments, Figure 8 As shown, as a preferred embodiment of the present invention, the antenna element 1 101A and the antenna element 2 101B are both shown in the manner of FIG300A;

[0122] Figure 8 The antenna element 1 101A and the antenna element 2 101B are placed side by side on the y-axis, and the electric field twisting element 104 adopts the waveguide wide-wall boss 202C. When the electric field polarization direction 301A inside 300A is the same as the y-axis direction, the initial phase is the same. In order to achieve the same polarization phase in the two-element antenna unit, the same electric field twisting element 104 should be used.

[0123] Embodiment 6: In some embodiments, Fig. 9As shown, as a preferred embodiment of the present invention, the antenna element 101A is shown in the manner of FIG300A, and the antenna element 2 101B is shown in the manner of FIG300B;

[0124] When the polarizations of the electric field 301A inside 300A and the electric field 301B inside 300B are both in the y-axis direction and their phases are opposite, in order to achieve the same polarization phase in the two-element antenna units, the electric field twisting elements 104 in the first branch and the second branch are mirrored about the yoz coordinate plane to compensate for the inversion of the initial transmission phase of the electric field 301B inside 300B.

[0125] Embodiment 7: In some embodiments, Figure 10-11 As shown, as a preferred embodiment of the present invention, this embodiment is a 4-unit center-fed antenna array, and the power splitting element 103 splits the signal into 4 paths on the narrow wall side. The output phase one 401A and the output phase two 401B after branching are (pi, 0, 0, pi) respectively. Therefore, the electric field twisting element 104 type adopts the (B, A, A, B) combination as the compensation phase, so that the combination of the four antenna elements is (300B, 300A, 300A, 300B) respectively.

[0126] In order to achieve antenna impedance matching within the working frequency band, a recess 403 is added to the waveguide transmission line 100 on the narrow wall of the waveguide.

[0127] Embodiment 8: In some embodiments, Figure 12-13 As shown, as a preferred embodiment of the present invention, this embodiment is a 4-unit center-fed antenna array, and the power splitting element 103 splits the signal into 4 paths on the wide wall side. The output phase one 401A and the output phase two 401B after branching are (0, pi, 0, pi) respectively. Therefore, the electric field twisting element 104 type adopts the (A, B, A, B) combination as the compensation phase, so that the combination of the four antenna elements is (300A, 300B, 300A, 300B) respectively.

[0128] In order to achieve antenna impedance matching within the working frequency band, a second recess 404 is added to the waveguide transmission line 100 on the narrow wall of the waveguide.

[0129] Embodiment 9: In some embodiments, Figure 14-15 As shown, as a preferred embodiment of the present invention, this embodiment is a 4-unit center-fed antenna array, and the power splitting element 103 performs signal splitting on the narrow wall side: 1 path is divided into 2 paths, and 2 paths are divided into 4 paths. The output phase 401A of the split paths is (0, 0, 0, 0) in sequence, and the electric field twisting element 104 type adopts the (A, A, A, A) combination, so that the combination of the four antenna elements is (300A, 300A, 300A, 300A) in sequence.

[0130] In order to achieve antenna impedance matching within the working frequency band, a recess 405 is added to the power splitter element 103 on the wide wall of the waveguide.

[0131] Embodiment 10: In some embodiments, Figure 16-Figure 17 As shown, as a preferred embodiment of the present invention, this embodiment is an 8-unit hybrid feeding type antenna array, and the power wave splitting element 103 performs signal splitting on the narrow wall side: 1 path is divided into 2 paths; the phase of the output after splitting is in phase;

[0132] The first branch has 4 units, the electric field twisting element 104 type adopts the combination of (A, A, A, A), the combination of antenna elements is (300A, 300A, 300A, 300A), and the spacing is 1 waveguide wavelength;

[0133] The second branch has 4 units, the electric field twisting element 104 type adopts the combination of (B, B, B, B), the combination of antenna elements is (300B, 300B, 300B, 300B), the spacing is 1 waveguide wavelength, and the spacing between adjacent 300A and 300B is half a waveguide wavelength.

[0134] In order to achieve antenna impedance matching within the working frequency band, a recess 406 is added on the wide wall of the power splitter element 103, so that a more focused beam pattern in the azimuth plane and the elevation plane can be achieved.

[0135] Embodiment 11: In some embodiments, Figure 18-19 As shown, as a preferred embodiment of the present invention, this embodiment is an 8-unit edge-fed antenna array, the power splitter element 103 performs signal transmission on the narrow wall side, the electric field twisting element 104 adopts a combination of (B, A, B, A, B, A, B, A), and the combination of antenna elements is (300B, 300A, 300B, 300A, 300B, 300A, 300B, 300A), with a spacing of 1 / 2 waveguide wavelength, which can achieve a more focused beam pattern in the pitch plane.

[0136] Embodiment 12: In some embodiments, Fig. 20 As shown, as a preferred embodiment of the present invention, in order to show the benefits of the implementation scheme of the present invention on antenna performance, the return loss results of antenna element 1 101A and antenna element 2 101B are given.

[0137] As shown in curve 500, the working bandwidth capability of the antenna is described based on the return loss being less than -10 dB. The present solution can achieve a bandwidth performance of 72-90 GHz, covering the 76-81 GHz bandwidth application range of automotive radar.

[0138] Embodiment 13: In some embodiments, Fig.21As shown, as a preferred embodiment of the present invention, Fig.21 The azimuth antenna pattern curve diagram 600 in the 76-81 GHz frequency band of an embodiment of the waveguide antenna device according to the present invention has the following main advantages:

[0139] (1) The 3dB beamwidth in the azimuth plane is better than 120° in a wideband, which meets the detection angle range of corner radar or surround radar;

[0140] (2) The beam is stable within the broadband, and there is no obvious distortion with frequency under gain fluctuation.

[0141] 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 miniaturized waveguide antenna device, characterized in that: The invention comprises an antenna device (1), wherein the antenna device (1) comprises a waveguide transmission line (100), a waveguide port (102), an antenna element 1 (101A), an antenna element 2 (101B), a power wave splitting element (103), an electric field twisting element (104) and a frame (105); A waveguide port (102) is provided on the left side of the waveguide transmission line (100), the waveguide port (102) is connected to the electronic system, and the waveguide port (102) is used to transmit and receive signals sent by the electronic system; The antenna element one (101A) and the antenna element two (101B) form an array combination in space, and the lower ends of the antenna element one (101A) and the antenna element two (101B) are connected to at least one waveguide transmission line (100); The power splitter element (103) is used to distribute power of a signal from an electronic system to achieve a focusing effect on the propagation signal in space. The power splitter element (103) is connected to at least one antenna element 1 (101A) and antenna element 2 (101B). The antenna element 1 (101A) and antenna element 2 (101B) are combined into an antenna array. The electric field twisting element (104) is used to twist the polarization direction of the electric field entering the antenna element 1 (101A) and the antenna element 2 (101B) from the waveguide transmission line (100) to meet the antenna polarization requirements in the radar system; a plurality of the electric field twisting elements (104) are provided, and the antenna element 1 (101A) and the antenna element 2 (101B) are respectively connected to one electric field twisting element (104); The geometrical axes of the antenna element 1 (101A) and the antenna element 2 (101B) are coaxial with the center of the electric field twisting element (104); The waveguide transmission line (100), the waveguide port (102), the antenna element one (101A), the antenna element two (101B), the power wave splitting element (103), and the electric field twisting element (104) are all arranged inside the frame (105).

2. The miniaturized waveguide antenna device according to claim 1, characterized in that: The cross section of the waveguide transmission line (100) is rectangular, and the cross section of the waveguide transmission line (100) is a closed pipe surrounded by wide walls and narrow walls.

3. The miniaturized waveguide antenna device according to claim 2, characterized in that: Antenna element one (101A) and antenna element two (101B) are rectangular open waveguides or horn-shaped open waveguides. The upper ends of antenna element one (101A) and antenna element two (101B) are radiation ports, and the cross-sectional shape of the radiation ports is rectangular. Antenna element one (101A) and antenna element two (101B) are both placed on the narrow wall of the waveguide transmission line (100), and the radiation port surfaces of antenna element one (101A) and antenna element two (101B) are both parallel to the narrow wall.

4. The miniaturized waveguide antenna device according to claim 3, characterized in that: Antenna element 1 (101A) and antenna element 2 (101B) are coaxially arranged in the array, and their axes are parallel to or orthogonal to the electric field polarization direction of the rectangular radiation aperture.

5. The miniaturized waveguide antenna device according to claim 4, characterized in that: The antenna array includes a center-fed type, an edge-fed type, and a hybrid-fed type; Center-fed type means 1 channel is divided into N channels, the typical value of N is 4, or other even values. After power splitting, the signals are centrally symmetrical, with equal amplitude and phase, or unequal amplitude and unequal phase. The edge-fed type is to connect M antenna elements in series, where the typical value of M is 4 or other integers. The hybrid feeding type includes two directions, which are orthogonal to each other on the plane, that is, the power splitting mode in one direction is the center feeding type, and the power splitting mode in the other direction is the edge end feeding type.

6. The miniaturized waveguide antenna device according to claim 5, characterized in that: There is a short-circuit point at the end of the waveguide transmission line (100), and the distance between the ends of antenna element 1 (101A) and antenna element 2 (101B) and the short-circuit point is 1 / 4 of the waveguide wavelength or an integral multiple thereof.

7. The miniaturized waveguide antenna device according to claim 6, characterized in that: In a coaxial array orthogonal to the electric field polarization direction, the characteristics of the adjacently arranged antenna element 1 (101A) and antenna element 2 (101B) are:

1. The phases of the waveguide transmission line (100) and the power wave splitting element (103) connected to the antenna element 1 (101A) and the antenna element 2 (101B) are the same after wave splitting. After adopting the electric field twisting element (104) with the same twisting direction, the electric field twisting direction is the same +90 degrees, or the same -90 degrees, resulting in the effect that the radiation polarization phases of the antenna element 1 (101A) and the antenna element 2 (101B) are the same phase; 2. The internal phases of the waveguide transmission line (100) and the power splitter element (103) connected to antenna element one (101A) and antenna element two (101B) are opposite after wave splitting. After using an electric field twisting element (104) with opposite twisting directions, one of the electric field twisting directions is +90 degrees and the other is -90 degrees, resulting in the radiation polarization phases of antenna element one (101A) and antenna element two (101B) being in phase.

8. The miniaturized waveguide antenna device according to claim 7, characterized in that: In a coaxial array parallel to the electric field polarization direction, the characteristics of the adjacently arranged antenna element 1 (101A) and antenna element 2 (101B) are:

1. After adopting the electric field twisting element (104) with the same polarization direction and the same phase, the arrangement spacing of the plurality of antenna elements one (101A) is 1 waveguide wavelength or the arrangement spacing of the plurality of antenna elements two (101B) is 1 waveguide wavelength, so that the radiation polarization phase of the antenna element one (101A) or the antenna element two (101B) is in phase; Second, after adopting the electric field twisting element (104) with the same twisting direction and opposite phase, the arrangement spacing of antenna element one (101A) and antenna element two (101B) is 1 / 2 times the waveguide wavelength, so that the radiation polarization phases of antenna element one (101A) and antenna element two (101B) are in phase.

9. The miniaturized waveguide antenna device according to claim 8, characterized in that: The method for achieving the same polarization direction and opposite phase of antenna element 1 (101A) and antenna element 2 (101B) is as follows:

1. The electric field twisting element (104) uses a deflected waveguide transmission line (202A), and the twisting angles are +α and -α respectively; 2. The electric field twisting element (104) adopts a rotated rectangular waveguide (202B), and the rotation angles are +α and -α respectively; Third, the electric field twisting element (104) uses a boss (202C) on the wide wall of the offset waveguide, and the boss (202C) is mirror-symmetric about the coordinate plane where the offset center 2 (206C) is located.

10. A method for twisting electric field of a miniaturized waveguide antenna device, used in the miniaturized waveguide antenna device of claim 9, characterized in that: The method is: One of the methods is: generating a deflected waveguide transmission line (202A) on the axis of the waveguide transmission line (100), wherein the deflection angle is α, and α is not 0; The second method is: placing an axially rotated rectangular waveguide (202B) on the axis of the waveguide transmission line (100), with a rotation angle of α, which is not 0; The third method is: a rectangular boss (202C) with a width of W is provided on the upper wide wall and the lower wide wall surface of the waveguide transmission line (100), and there is an offset O between the center positions of the two.

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