Planar waveguide slot antenna unit

Abstract

A slab waveguide slot antenna unit provided by the present invention comprises a radiation unit, an excitation unit and a feed unit, the radiation unit comprises a radiation square cavity and a radiation slot, the excitation unit comprises an excitation square cavity and an excitation slot, the feed unit comprises a feed square cavity and a feed slot, and the feed slot is connected with the excitation square cavity. According to the invention, a special radiation slot design is adopted, so that the radiation aperture efficiency is improved, more input energy can be effectively radiated into a free space, and the transmitting and receiving efficiency of the antenna is improved; the antenna comprises the gaps in the excitation square cavity and the feed square cavity, so that the feed structure is simplified, the antenna is easier to manufacture and maintain, and the cost and the complexity are reduced; the simplification of the feed structure also helps to improve the stability and reliability of the antenna. The whole waveguide antenna has axial symmetry, so that manufacturing and adjustment are more convenient. And the axisymmetric structure is beneficial to keeping the symmetry and consistency of the antenna, so that the stability of the performance is improved.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a planar waveguide slot antenna unit. Background Art

[0002] Waveguide antennas are an important class of electromagnetic radiation and reception devices, which are widely used in high-frequency and microwave frequency communications, radar, astronomy, medical equipment, etc. The design and performance of waveguide antennas are critical to the successful operation of these applications.

[0003] In the field of antenna technology, researchers have been working hard to find new methods to improve antenna performance, simplify the structure and meet the growing application needs. Traditional waveguide antennas usually have one radiating structure corresponding to one feeding structure. After forming an array, the feeding structure is complex, the volume and weight increase, which limits its production feasibility and application scope. Summary of the invention

[0004] Traditional waveguide antennas are complex to design and manufacture, involve multiple components, and limit production feasibility and application scope. A planar waveguide slot antenna unit is provided to improve radiation aperture efficiency and simplify the feeding structure. The present invention adopts a unique cavity structure and slot design to achieve these goals, bringing new possibilities for high frequency and microwave frequency band applications.

[0005] The present invention provides a planar waveguide slot antenna unit, comprising a radiation unit, an excitation unit and a feeding unit connected in sequence from top to bottom, wherein the radiation unit comprises a radiation slot and a radiation square cavity connected to the bottom of the radiation slot, the excitation unit comprises an excitation slot and an excitation square cavity connected to the bottom of the excitation slot, and the feeding unit comprises a feeding slot and a feeding square cavity connected to the bottom of the feeding slot; the excitation slot is connected to the bottom of the radiation square cavity, and the feeding slot is connected to the bottom of the excitation square cavity;

[0006] The radiation slit is located on the diagonal line of the radiation square cavity and is rotationally symmetrical about the axis of the radiation square cavity. The radiation square cavity is a cube with equal length and width, and the excitation slit is a cross slit.

[0007] The radiation slot, the radiation square cavity, the excitation slot and the feeding slot are all axially symmetrical structures with an axis perpendicular to the center point of the upper surface of the excitation square cavity. The excitation slot is coaxially symmetrical with the radiation square cavity, and the feeding slot is coaxially symmetrical with the excitation square cavity.

[0008] The ratio of the number of feeding slots to the number of excitation slots is 1:4, and the ratio of the number of excitation slots to the number of radiation slots is 1:4;

[0009] The signal enters the feeding slot through the feeding square cavity, is then sent into the excitation square cavity through the feeding slot, and is then sent into the radiating square cavity through the excitation slot. The radiating slot couples the signal from the radiating square cavity and radiates it into free space.

[0010] The planar waveguide slot antenna unit described in the present invention, as a preferred embodiment, has four radiating square cavities, which are symmetrically connected to the top of the excitation slot, and each radiating square cavity is connected to four radiating slots;

[0011] The number of the excitation slits is 4, which are located at the four corners of the excitation square cavity and are rotationally symmetrical about the axis of the excitation square cavity;

[0012] The center of the feeding slit coincides with the central axis of the excitation square cavity.

[0013] The planar waveguide slot antenna unit described in the present invention is, as a preferred embodiment, a planar waveguide slot unit antenna that is linearly polarized and the polarization is parallel to the narrow side of the feed slot.

[0014] In the planar waveguide slot antenna unit described in the present invention, as a preferred embodiment, the radiation slot is a pattern formed by splicing a cube and two semi-cylinders, which is obtained by rotating the symmetry axis of the radiation square cavity 90° four times along the z-axis direction;

[0015] When the number of radiation square cavities is 4, the radiation slit is obtained by rotating the figure composed of a cube and two semi-cylinders four times along the symmetry axis of the radiation square cavity in the z-axis direction by 90° and then rotating the figure four times along the symmetry axis of the excitation square cavity in the z-axis direction by 90°.

[0016] The planar waveguide slot antenna unit described in the present invention is preferably configured such that the four edges of the radiating square cavity in the direction parallel to the z-axis are all rounded;

[0017] When the number of the radiation square cavities is 4, the radiation square cavity is obtained by rotating the symmetry axis of the excitation square cavity along the z-axis direction by 90° four times.

[0018] The planar waveguide slot antenna unit described in the present invention is preferably formed by merging the excitation slots after the cube is chamfered and rotated 90° along its own z-axis symmetry line;

[0019] When the number of the radiation square cavities is 4, the number of the cross slits is also 4, which is obtained by rotating the symmetry axis of the excitation square cavity along the z-axis direction by 90° four times.

[0020] In the planar waveguide slot antenna unit described in the present invention, as a preferred embodiment, the four corners of the excitation square cavity are chamfered.

[0021] In the planar waveguide slot antenna unit described in the present invention, as a preferred embodiment, the feeding square cavity is a special-shaped waveguide cavity with a cut corner, and the feeding slot is connected to the upper side of the cut corner.

[0022] The planar waveguide slot antenna unit described in the present invention, as a preferred embodiment, the feeding square cavity includes a body and a first cut corner and a second cut corner respectively connected to two sides of the body;

[0023] The first cut angle is located at the lower left end of the body, and the height of the cut angle is less than the total height of the body. The second cut angle is located at the lower right part of the body, and the height is the same as the total height of the body.

[0024] The feeding slit is located on the upper side of the first cut corner.

[0025] The planar waveguide slot antenna unit described in the present invention is preferably configured such that the minimum distance between the feeding slot and the body in the x direction is 0.425 mm, and the shortest distance in the y direction is 0.62 mm; the feeding slot is a cube with a height of 1 mm, a length of 4.85 mm, and a width of 1.6 mm, chamfered with a chamfer radius of 0.5 mm, and four sides along the z-axis direction of the body are parallel;

[0026] The main body is a cuboid of 5.69mm*8.69mm*1.4225mm. The length of the first cutting angle in the x-direction is 0.8mm, the length in the y-direction is 5.69mm, and the height in the z-direction is 0.5mm. The length of the second cutting angle in the x-direction is 0.3mm, and the length in the y-direction is 4mm.

[0027] In view of the complex structure and performance challenges of traditional waveguide antennas, the present invention discloses a planar waveguide slot antenna unit, which is composed of a radiation unit, an excitation unit and a feeding unit, wherein the radiation unit includes a radiation square cavity and a radiation slot, wherein the excitation unit includes an excitation square cavity and an excitation slot, wherein the feeding unit is composed of a feeding square cavity and a feeding wave slot, which is connected to the excitation square cavity, and the signal enters the feeding slot through the waveguide feeding square cavity, and then is sent to the excitation square cavity through the feeding slot, and then is sent to the radiation square cavity through the excitation slot, and the radiation slot couples the signal from the radiation square cavity and radiates it into free space. The planar waveguide slot antenna unit of the present invention has a compact feeding structure, a low profile, is easy to form a large-scale array, and is easy to process.

[0028] The excitation slot of the present invention determines the linear polarization state of the antenna. The special slot design of the excitation square cavity and the feeding square cavity simplifies the feeding structure, making it more suitable for production. The entire planar waveguide slot unit structure has axisymmetry, which increases the convenience of manufacturing and adjustment.

[0029] The present invention has the following advantages:

[0030] (1) The planar waveguide slot unit structure of the present invention adopts a special radiation slot design, which improves its radiation aperture efficiency, so that more input energy can be effectively radiated into free space, thereby improving the transmission and reception efficiency of the antenna.

[0031] (2) The present invention adopts a unique slot design, including slots in the excitation cavity and the feeding cavity, thereby simplifying the feeding structure; this simplification makes the antenna easier to manufacture and maintain, reducing cost and complexity; in addition, the simplification of the feeding structure also helps to improve the stability and reliability of the antenna. The entire waveguide antenna has axial symmetry, which makes manufacturing and adjustment more convenient. The axial symmetric structure helps to maintain the symmetry and consistency of the antenna, thereby improving the stability of the performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 It is a left side view of a planar waveguide slot antenna unit;

[0033] Figure 2 A top view of a planar waveguide slot antenna unit;

[0034] Figure 3 is a perspective view of a planar waveguide slot antenna unit;

[0035] Figure 4 It is a perspective schematic diagram of a feeding unit of a planar waveguide slot antenna unit;

[0036] Figure 5 It is a schematic diagram of the feeding square cavity structure of a planar waveguide slot antenna unit;

[0037] Figure 6 It is a schematic diagram of the amplitude curve of the S parameters of Example 1 of a planar waveguide slot antenna unit.

[0038] Reference numerals:

[0039] 1. Radiating slit; 2. Radiating square cavity; 3. Excitation slit; 4. Excitation square cavity; 5. Feeding slit; 6. Feeding square cavity; 61. Main body; 62. First cutting angle; 63. Second cutting angle. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0041] Example 1

[0042] like Figures 1 to 5As shown, a planar waveguide slot antenna unit includes a radiation unit, an excitation unit and a feeding unit, wherein the radiation unit includes a radiation square cavity 2 and a radiation slot 1, wherein the excitation unit includes an excitation square cavity 4 and an excitation slot 3, wherein the feeding unit consists of a feeding square cavity 6 and a feeding slot 5; four radiation slots 1 are opened on the upper surface of the four corners of the radiation square cavity 2, and the radiation slots 1 are symmetrically distributed on the upper plane of the radiation square cavity 2 about the center point of the upper plane of the radiation square cavity 2, four excitation slots 3 are opened on the upper surface of the four corners of the excitation square cavity 4, the excitation slots 3 connect the excitation square cavity 4 and the radiation square cavity 2, and a feeding slot 5 is opened on the upper surface of the feeding square cavity 6.

[0043] The entire planar waveguide slot unit, except for the feeding square cavity 6, includes a radiation slot 1, a radiation square cavity 2, an excitation square cavity 4, an excitation slot 3, and a feeding slot 5, which are axially symmetrical about an axis perpendicular to the center point of the upper surface of the excitation square cavity 4, wherein the excitation slot 3 is coaxially symmetrical with the radiation square cavity 2, and the feeding slot 5 is coaxially symmetrical with the excitation square cavity 4.

[0044] The working principle of a planar waveguide slot unit of the present invention is as follows:

[0045] The signal enters the feeding slot 5 through the waveguide feeding cavity 6, and is then sent to the excitation cavity 4 through the feeding slot 5, and then sent to the radiation cavity 2 through the excitation slot 3. The radiation slot 1 couples the signal from the radiation cavity 2 and radiates it into the free space to form the required radiation pattern.

[0046] The S parameter curve of the Ka-band planar waveguide slot unit with frequency is as follows: Figure 6As shown. The relevant dimensions of the waveguide antenna are as follows: the radiation slot 1 is a cube with a height of 1mm, a length of 3.32mm, and a width of 1.58mm and two semi-cylinders with a height of 1mm and a radius of 0.79mm, which is obtained by rotating 90° four times along the z-axis symmetry axis of the radiation square cavity 2, and then rotating 90° four times along the z-axis symmetry axis of the excitation square cavity 4; the radiation square cavity 2 is a cube with a height of 1.6mm, a length and a width of 9.1mm, and the four sides parallel to the z-axis are chamfered with a chamfer radius of 0.5mm, and the figure is obtained by rotating 90° four times along the z-axis symmetry axis of the radiation square cavity 2; the excitation slot 3 is a cube with a height of 1mm, a length of 4.2mm, and a width of 1. A 25mm cube is chamfered with a radius of 0.5mm on the four sides parallel to the z-axis, and then rotated 90° along its own z-axis symmetry line to form a combined figure, which is then rotated 90° four times along the z-axis symmetry axis of the excitation square cavity 4; the excitation square cavity 4 is a cube with a height of 4.58mm, a length and a width of 14.8mm, which is chamfered with a chamfer radius of 0.5mm and four sides parallel to the z-axis; the feed slit 5 is a cube with a height of 1mm, a length of 4.85mm, and a width of 1.6mm, which is chamfered with a chamfer radius of 0.5mm, and the four sides along the z-axis are parallel; the feed slit 5 is 0.62mm away from the surface where dz1 is located, and 0.425mm away from the surface opposite to dx1;

[0047] Feeding cavity 6 Figure 5 As shown, it includes a main body 61 and a first cut corner 62 and a second cut corner 63 respectively connected to both sides of the main body 61, wherein dx1 of the main body 61 is 5.69mm, dy1 is 8.69mm, dz1 is 1.4225mm, dx2 of the first cut corner 62 is 0.8mm, dy2 is 5.69mm, dz2 is 0.9225mm, and dx3 of the second cut corner 63 is 0.3mm, and dy3 is 4mm.

[0048] The implementation effect of this embodiment is as follows Figure 6 As shown, the standing wave ratio is less than 2 in the range of 34 GHz to 36 GHz.

[0049] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A planar waveguide slot antenna unit, characterized in that: The invention comprises a radiation unit, an excitation unit and a feeding unit which are connected in sequence from top to bottom, wherein the radiation unit comprises a radiation slot (1) and a radiation square cavity (2) connected to the bottom of the radiation slot (1), the excitation unit comprises an excitation slot (3) and an excitation square cavity (4) connected to the bottom of the excitation slot (3), and the feeding unit comprises a feeding slot (5) and a feeding square cavity (6) connected to the bottom of the feeding slot (5); the excitation slot (3) is connected to the bottom of the radiation square cavity (2), and the feeding slot (5) is connected to the bottom of the excitation square cavity (4); The radiation slit (1) is located on the diagonal line of the radiation square cavity (2) and is rotationally symmetrical about the axis of the radiation square cavity (2); the radiation square cavity (2) is a cube with equal length and width; and the excitation slit (3) is a cross slit; The radiation slit (1), the radiation square cavity (2), the excitation slit (3), and the feeding slit (5) are all axially symmetrical structures with an axis perpendicular to the center point of the upper surface of the excitation square cavity (4); the excitation slit (3) is coaxially symmetrical with the radiation square cavity (2), and the feeding slit (5) is coaxially symmetrical with the excitation square cavity (4); The ratio of the number of the feeding slits (5) to the number of the excitation slits (3) is 1:4, and the ratio of the number of the excitation slits (3) to the number of the radiation slits (1) is 1:4; The signal enters the feeding slit (5) through the feeding square cavity (6), is then sent into the excitation square cavity (4) through the feeding slit (5), and is then sent into the radiation square cavity (2) through the excitation slit (3); the radiation slit (1) couples the signal out of the radiation square cavity (2) and radiates it into free space.

2. A planar waveguide slot antenna unit according to claim 1, characterized in that: The number of the radiation square cavities (2) is four, and they are symmetrically connected to the top of the excitation slits (3), and each of the radiation square cavities (2) is connected to four of the radiation slits (1); The number of the excitation slits (3) is four, which are located at four corners of the excitation square cavity (4) and are rotationally symmetrical about the axis of the excitation square cavity (4); The center of the feeding slit (5) coincides with the central axis of the excitation square cavity (4).

3. The planar waveguide slot antenna unit according to claim 1, characterized in that: The planar waveguide slot unit antenna is linearly polarized and the polarization is parallel to the narrow side of the feeding slot (5).

4. The planar waveguide slot antenna unit according to claim 1, characterized in that: The radiation slit (1) is a figure formed by splicing a cube and two semi-cylinders, which is obtained by rotating the symmetry axis of the radiation square cavity (2) 90° four times along the z-axis direction; When the number of the radiation square cavities (2) is four, the radiation slit (1) is obtained by rotating a pattern formed by splicing a cube and two semi-cylinders four times along the symmetry axis of the radiation square cavity (2) in the z-axis direction by 90°, and then rotating four times along the symmetry axis of the excitation square cavity (4) in the z-axis direction by 90°.

5. The planar waveguide slot antenna unit according to claim 1, characterized in that: The four edges of the radiation square cavity (2) in the direction parallel to the z-axis are all rounded; When the number of the radiation square cavities (2) is four, the radiation square cavity (2) is obtained by rotating the symmetry axis of the excitation square cavity (4) along the z-axis direction by 90° four times.

6. The planar waveguide slot antenna unit according to claim 1, characterized in that: The excitation slit (3) is obtained by chamfering a cube and rotating it 90° along its own z-axis symmetry line and then merging them; When the number of the radiation square cavities (2) is four, the number of the cross slits is also four, obtained by rotating the symmetry axis of the excitation square cavity (4) along the z-axis direction by 90° four times.

7. The planar waveguide slot antenna unit according to claim 1, characterized in that: The four corners of the excitation square cavity (4) are all chamfered.

8. The planar waveguide slot antenna unit according to claim 1, characterized in that: The feeding square cavity (6) is a shaped waveguide cavity with a cut corner, and the feeding slit (5) is connected to one side above the cut corner.

9. The planar waveguide slot antenna unit according to claim 8, characterized in that: The feeding square cavity (6) comprises a body (61) and a first cut corner (62) and a second cut corner (63) respectively connected to two sides of the body (61); The first cut corner (62) is located at the lower left end of the body (61), and the height of the cut corner is less than the total height of the body (61); the second cut corner (63) is located at the lower right part of the body (61), and the height is the same as the total height of the body (61); The feeding slit (5) is located on one side above the first cut corner (62).

10. The planar waveguide slot antenna unit according to claim 9, characterized in that: The minimum distance between the feeding slit (5) and the main body (61) in the x direction is 0.425 mm, and the shortest distance in the y direction is 0.62 mm; the feeding slit (5) is a cube with a height of 1 mm, a length of 4.85 mm, and a width of 1.6 mm, chamfered with a chamfer radius of 0.5 mm, and four sides along the z-axis direction of the main body (61) are parallel; The main body (61) is a cuboid of 5.69mm*8.69mm*1.4225mm; the first cut corner (62) has an x-direction length of 0.8mm, a y-direction length of 5.69mm, and a z-direction height of 0.5mm; the second cut corner (63) has an x-direction length of 0.3mm and a y-direction length of 4mm.

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