Dual-polarization complementary millimeter wave antenna

Abstract

The invention discloses a dual-polarization complementary millimeter wave antenna, and belongs to the technical field of wireless communication. The antenna sequentially comprises a first dielectric layer, a second bonding layer, a third dielectric layer, a fourth bonding layer, a fifth dielectric layer, a sixth bonding layer and a seventh dielectric layer from top to bottom. The upper surface of the first dielectric layer is provided with metal patches which are symmetrical about the center and are in a butterfly shape, each metal patch comprises a trapezoidal dipole structure and a square annular structure, each trapezoidal dipole structure comprises two trapezoidal patches, and a first antenna feeder and a second antenna feeder are led out from the long sides of the two trapezoidal patches to the edge of the first dielectric layer respectively. A differential feed network is formed; the upper surface of the fifth dielectric layer is antenna reference ground, an H-shaped gap is formed in the center of the fifth dielectric layer, and the lower surface of the fifth dielectric layer is a third antenna feeder; the lower surface of the seventh dielectric layer is feeder reference ground; the fifth dielectric layer is provided with an array structure composed of a plurality of short-circuit metal columns, the upper end of the array structure composed of the short-circuit metal columns is connected with the antenna reference ground, and the lower end of the array structure is connected with the feeder line reference ground.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications, and in particular relates to a dual-polarization complementary millimeter wave antenna. Background Art

[0002] With the rapid development of 5G communication technology, millimeter wave communication has attracted widespread attention due to its high-speed data transmission capability and broadband characteristics. The planar complementary antenna composed of a dipole and a loop antenna has excellent characteristics such as broadband and flat gain. However, the antenna uses a coplanar waveguide to excite the dipole antenna, which will destroy the symmetry of the antenna radiation pattern, reduce the stability of the input impedance, and can only transmit and receive electromagnetic waves of a single polarization. Nowadays, whether in high-end wireless communications or in military and radar systems, higher requirements are placed on data transmission rate, reliability, and signal anti-interference ability. In many buildings and complex electromagnetic environments, single-polarized signals are easily absorbed and reflected by objects such as walls and trees during transmission, and the polarization direction changes, resulting in signal amplitude fading, delay spread, Doppler effect, etc., resulting in reduced system reliability. In addition, the single-polarized antenna can only receive electromagnetic waves in a specific direction, and has a weak ability to handle multipath effects, which may also lead to signal attenuation and interference problems. For this reason, a dual-polarized complementary millimeter wave antenna is proposed. Summary of the invention

[0003] In view of the deficiencies in the prior art, an object of the present invention is to provide a dual-polarization complementary millimeter wave antenna to solve the problems in the prior art.

[0004] The purpose of the present invention can be achieved through the following technical solutions:

[0005] A dual-polarization complementary millimeter wave antenna, comprising, from top to bottom, a first dielectric layer, a second bonding layer, a third dielectric layer, a fourth bonding layer, a fifth dielectric layer, a sixth bonding layer, and a seventh dielectric layer;

[0006] A butterfly-shaped metal patch is provided on the upper surface of the first dielectric layer, which is symmetrical about the center. The metal patch includes a trapezoidal dipole structure and a square ring structure. The trapezoidal dipole structure includes two trapezoidal patches, and the square ring structure includes two square rings. The long sides of the two trapezoidal patches lead out the first antenna feed line and the second antenna feed line respectively toward the edge of the first dielectric layer, forming a differential feeding network.

[0007] The upper surface of the fifth dielectric layer is the antenna reference ground, and an H-shaped gap is opened at the center position thereof; the lower surface of the fifth dielectric layer is the third antenna feeder; the lower surface of the seventh dielectric layer is the feeder reference ground; an array structure composed of a plurality of short-circuited metal columns is arranged on the fifth dielectric layer, and the array structure composed of the short-circuited metal columns is connected to the antenna reference ground at the upper end and to the feeder reference ground at the lower end.

[0008] Furthermore, the distance between the bottoms of the two trapezoidal patches is 1 medium wavelength λ g , the total length of the two square rings in the square ring structure is 1 free wavelength λ0, and the trapezoidal dipole and the square ring form a closed structure.

[0009] Furthermore, the H-shaped slot is perpendicular to the third antenna feeder line, and the H-shaped slot is perpendicular to the short straight side of the trapezoidal dipole structure.

[0010] Furthermore, the centers of the metal patch, the H-shaped gap, and the array structure consisting of the short-circuit metal columns coincide with each other.

[0011] Furthermore, the center lines of the widths of the first antenna feed line and the second antenna feed line coincide with the center lines of the long straight sides of the trapezoidal dipole structure.

[0012] Furthermore, the first dielectric layer, the third dielectric layer, the fifth dielectric layer, and the seventh dielectric layer adopt a substrate with a dielectric constant of 3.66 and a loss tangent of 0.004, and a thickness of 101 um;

[0013] The second bonding layer, the fourth bonding layer and the sixth bonding layer are made of plates with a dielectric constant of 3.52, a loss tangent of 0.004 and a thickness of 202um.

[0014] Further, in the trapezoidal dipole structure, the upper base length of the trapezoidal patch is 1.3 mm, the lower base length is 1.8 mm, the height is 1.23 mm, and the distance between the upper bases of the two trapezoidal patches in the trapezoidal dipole structure is 0.44 mm;

[0015] In the square ring structure, the side length of the square ring is 1.15 mm, the width of the outward extension is 0.08 mm, and isosceles right triangles with a side length of 0.06 mm are cut off at the four corners.

[0016] Furthermore, a pair of parallel microstrip lines with a width of 0.08 mm and a length of 0.175 mm are provided at the connection between the trapezoidal dipole structure and the square ring structure.

[0017] Furthermore, the length of the H-shaped gap transverse groove is 1.1 mm, and the width is 0.2 mm, and the length of the vertical grooves on both sides of the transverse groove is 0.9 mm, and the width is 0.3 mm.

[0018] Furthermore, the diameter of the short-circuit metal column is not greater than λ0 / 10, and the distance between the centers of two adjacent short-circuit metal columns is not greater than twice the diameter of the short-circuit metal column.

[0019] Beneficial effects of the present invention:

[0020] 1. The dual-polarization complementary millimeter wave antenna of the present invention realizes the dual-polarization function through reasonable structural design and dielectric stacking setting, and has the characteristics of broadband and high isolation. The antenna is suitable for wireless communication systems in the millimeter wave frequency band and has broad application prospects.

[0021] 2. The dual-polarized complementary millimeter-wave antenna of the present invention adopts a substrate integrated waveguide (SIW) cavity composed of short-circuited metal columns to improve the problem of excessive backward radiation when the H-shaped slot is coupled and fed, thereby effectively expanding the antenna's -10dB impedance bandwidth and improving the antenna's in-band gain.

[0022] 3. The dual-polarization complementary millimeter wave antenna of the present invention combines slot feeding and coaxial feeding methods. While realizing dual polarization, the polarization isolation between the horizontal and vertical directions is better than 35dB, ensuring the reliability and stability of communication.

[0023] 4. The dual-polarized complementary millimeter wave antenna of the present invention forms a closed-loop antenna with a trapezoidal dipole and a square ring, achieving the characteristic of antenna broadband while satisfying the gain flatness. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] 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 description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 It is a schematic diagram of the three-dimensional structure of the dual-polarization complementary millimeter wave antenna in the present invention;

[0026] Figure 2 A top view of the dual-polarization complementary millimeter wave antenna structure of the present invention;

[0027] Figure 3 It is a side view of the dual-polarization complementary millimeter wave antenna structure of the present invention;

[0028] Figure 4 It is a simulation result diagram of the return loss of the dual-polarization complementary millimeter wave antenna in two polarization directions in the present invention;

[0029] Figure 5 This is a simulation result diagram of the isolation of the dual-polarization complementary millimeter wave antenna at two polarization ports in the present invention;

[0030] Figure 6 This is a simulation result diagram of the current distribution in two polarization directions of the dual-polarization complementary millimeter wave antenna at the center frequency of the present invention;

[0031] Figure 7is the radiation pattern of the dual-polarization complementary millimeter wave antenna in the present invention in two polarization directions;

[0032] In the figure: 1-first dielectric layer, 2-second adhesive layer, 3-third dielectric layer, 4-fourth adhesive layer, 5-antenna reference ground, 6-fifth dielectric layer, 7-sixth adhesive layer, 8-seventh dielectric layer, 9-feeder reference ground, 10-first antenna feeder, 11-metal patch, 12-second antenna feeder, 13-H-shaped gap, 14-short-circuit metal column, 15-third antenna feeder. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] like Figures 1 to 3 As shown, a dual-polarization complementary millimeter wave antenna includes, from top to bottom, a first dielectric layer 1, a second bonding layer 2, a third dielectric layer 3, a fourth bonding layer 4, a fifth dielectric layer 6, a sixth bonding layer 7, and a seventh dielectric layer 8;

[0035] A butterfly-shaped metal patch 11 is provided on the upper surface of the first dielectric layer 1 and is symmetrical about the center. The metal patch 11 includes a trapezoidal dipole structure and a square ring structure. The trapezoidal dipole structure includes two trapezoidal patches, and the square ring structure includes two square rings.

[0036] The two long sides of the trapezoid in the trapezoidal dipole structure lead out the first antenna feed line 10 and the second antenna feed line 12 to the edge of the first dielectric layer 1, respectively, to form a differential feeding network, thereby realizing energy coupling feeding in the horizontal direction of the antenna; the trapezoidal dipole structure and the square ring structure form a closed structure, thereby realizing a centrally symmetrical complementary antenna.

[0037] The distance between the bottom edges of the two trapezoidal patches is 1 medium wavelength λ g The total length of the two square rings in the square ring structure is 1 free wavelength λ0, and the trapezoidal dipole and the square ring form a closed structure to realize a centrally symmetrical complementary antenna.

[0038] The upper surface of the fifth dielectric layer 6 is the antenna reference ground 5, and an H-shaped slot 13 is provided at the center thereof to realize a vertical energy coupling feeder. The lower surface of the fifth dielectric layer 6 is the third antenna feeder 15; the H-shaped slot 13 is perpendicular to the third antenna feeder 15 and is also perpendicular to the short side of the trapezoidal dipole structure in the metal patch 11.

[0039] The lower surface of the seventh dielectric layer 8 is the feeder reference ground 9; an array structure composed of a plurality of short-circuit metal columns 14 is provided on the fifth dielectric layer 6, and the array structure composed of short-circuit metal columns 14 is connected to the antenna reference ground 5 at the upper end and the feeder reference ground 9 at the lower end.

[0040] The center of the array structure composed of the metal patch 11, the H-shaped gap 13, and the short-circuit metal column 14 coincides, and the center line of the width of the first antenna feed line 10 and the second antenna feed line 10 coincides with the center line of the long straight side of the trapezoidal dipole structure.

[0041] In this embodiment, the first dielectric layer 1, the third dielectric layer 3, the fifth dielectric layer 6, and the seventh dielectric layer 8 use a substrate with a dielectric constant of 3.66 and a loss tangent of 0.004, and its thickness is set to 101um; the second bonding layer 2, the fourth bonding layer 4, and the sixth bonding layer 7 use a plate with a dielectric constant of 3.52 and a loss tangent of 0.004, and its thickness is set to 202um.

[0042] In this embodiment, for the trapezoidal dipole structure, the upper base length of the trapezoidal patch is 1.3 mm, the lower base length is 1.8 mm, the height is 1.23 mm, and the distance between the upper bases of the two trapezoidal patches is 0.44 mm;

[0043] For the square ring structure, the side length of the square ring is 1.15mm, the width of the outward extension is 0.08mm, and isosceles right triangles with a side length of 0.06mm are cut off at the four corners to reduce the width of the microstrip line at the bend, thereby increasing the characteristic impedance at the right-angle bend and reducing the discontinuity effect at the bend;

[0044] A pair of parallel microstrip lines with a width of 0.08 mm and a length of 0.175 mm are provided at the connection between the trapezoidal dipole structure and the square ring structure to improve the return loss and the antenna radiation performance.

[0045] In this embodiment, the length of the horizontal groove of the H-shaped slot 13 is 1.1 mm, and the width is 0.2 mm, and the length of the vertical grooves on both sides of the horizontal groove is 0.9 mm, and the width is 0.3 mm.

[0046] In this embodiment, the diameter of the short-circuit metal column 14 is 0.2 mm to meet the requirement of not more than λ0 / 10 (λ0 is the free wavelength), and the distance between the centers of two adjacent short-circuit metal columns 14 is 0.3 mm, which is not more than twice the diameter of the short-circuit metal column 14. The array structure composed of the short-circuit metal columns 14 serves as the vertical wall of the planar cavity, and forms a substrate integrated waveguide (SIW) cavity with the antenna reference ground 5 and the feeder reference ground 9, which improves the problem of excessive backward radiation when the H-shaped slot 13 is coupled and fed, thereby effectively expanding the antenna -10dB impedance bandwidth and improving the antenna in-band gain.

[0047] Figure 4 This is the simulation result of the return loss of the butterfly antenna in two polarization directions. From the simulation results, it can be seen that the -10dB impedance bandwidth of the antenna in the horizontal polarization direction is 7.81GHz (58.17GHz~65.98GHz), and the relative bandwidth is 13.03%; the -10dB impedance bandwidth in the vertical polarization direction is 10.31GHz (55.72GHz~66.03GHz), and the relative bandwidth is 17%, indicating that the antenna can effectively radiate energy in a wider frequency band in both polarization directions.

[0048] Figure 5 This is a simulation result diagram of the polarization isolation of the butterfly antenna at two polarization ports. From the simulation results, it can be seen that the isolation of the antenna within the bandwidth is greater than 35dB, and the interference in the two polarization directions is significantly reduced, which helps to improve the communication quality and ensure the reliability and stability of the communication link in practical applications.

[0049] Figure 6 This is the simulation result of the current distribution in two polarization directions of the butterfly antenna at the center frequency. From the simulation results, we can know that: Figure 6 As shown in (a) in the horizontal polarization direction, the currents on the square ring of the antenna cancel each other out, and the currents excited at the long sides of the trapezoidal dipole are in the same direction, radiating energy outward; Figure 6 As shown in (b), in the vertical polarization direction, the currents on the antenna trapezoidal dipole cancel each other out, and the currents excited by the square ring are in the same direction, radiating energy outward.

[0050] Figure 7 is the radiation pattern of the horizontal polarization and vertical polarization of the butterfly antenna at the center frequency. From the simulation results, it can be seen that: Figure 7 As shown in (a) in the horizontal polarization direction, the half-power beamwidth of the antenna on the E plane is 26.59°, and the half-power beamwidth on the H plane is 104.9°; Figure 7 As shown in (b), in the vertical polarization direction, the half-power beamwidth of the antenna in the E plane is 42.54°, and the half-power beamwidth in the H plane is 79.93°. This means that the antenna has a wide coverage range in both the E plane and the H plane, and exhibits significant symmetry.

[0051] In the description of this specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0052] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, and these changes and improvements all fall within the scope of the present invention to be protected.

Claims

1. A dual-polarization complementary millimeter wave antenna, characterized in that: The invention comprises, from top to bottom, a first dielectric layer (1), a second bonding layer (2), a third dielectric layer (3), a fourth bonding layer (6), a fifth dielectric layer (6), a sixth bonding layer (7), and a seventh dielectric layer (8); A butterfly-shaped metal patch (11) is provided on the upper surface of the first dielectric layer (1) and is symmetrical about the center. The metal patch (11) comprises a trapezoidal dipole structure and a square ring structure. The trapezoidal dipole structure comprises two trapezoidal patches, and the square ring structure comprises two square rings. The long sides of the two trapezoidal patches lead out a first antenna feed line (10) and a second antenna feed line (12) respectively toward the edge of the first dielectric layer (1), forming a differential feeding network. The upper surface of the fifth dielectric layer (6) is the antenna reference ground (5), and an H-shaped gap (13) is provided at the center thereof; the lower surface of the fifth dielectric layer (6) is the third antenna feeder (15); the lower surface of the seventh dielectric layer (8) is the feeder reference ground (9); an array structure composed of a plurality of short-circuit metal columns (14) is provided on the fifth dielectric layer (6); the array structure composed of the short-circuit metal columns (14) is connected to the antenna reference ground (5) at the upper end and to the feeder reference ground (9) at the lower end.

2. A dual-polarization complementary millimeter wave antenna according to claim 1, characterized in that: The distance between the bottoms of the two trapezoidal patches is 1 medium wavelength λ g , the total length of the two square rings in the square ring structure is 1 free wavelength λ0, and the trapezoidal dipole and the square ring form a closed structure.

3. A dual-polarization complementary millimeter wave antenna according to claim 1, characterized in that: The H-shaped slot (13) is perpendicular to the third antenna feeder line (15), and the H-shaped slot (13) is perpendicular to the short straight side of the trapezoidal dipole structure.

4. A dual-polarization complementary millimeter wave antenna according to claim 1, characterized in that: The centers of the metal patch (11), the H-shaped gap (13) and the array structure composed of short-circuit metal columns (14) coincide with each other.

5. The dual-polarization complementary millimeter wave antenna according to claim 1, characterized in that: The center lines of the widths of the first antenna feed line (10) and the second antenna feed line (12) coincide with the center lines of the long straight sides of the trapezoidal dipole structure.

6. The dual-polarization complementary millimeter wave antenna according to claim 1, characterized in that: The first dielectric layer (1), the third dielectric layer (3), the fifth dielectric layer (6) and the seventh dielectric layer (8) are made of a substrate with a dielectric constant of 3.66 and a loss tangent of 0.004, and a thickness of 101 um; The second bonding layer (2), the fourth bonding layer (4) and the sixth bonding layer (7) are made of a plate material with a dielectric constant of 3.52 and a loss tangent of 0.004, and a thickness of 202 um.

7. A dual-polarization complementary millimeter wave antenna according to claim 1 or 6, characterized in that: In the trapezoidal dipole structure, the upper base length of the trapezoidal patch is 1.3 mm, the lower base length is 1.8 mm, the height is 1.23 mm, and the distance between the upper bases of the two trapezoidal patches in the trapezoidal dipole structure is 0.44 mm; In the square ring structure, the side length of the square ring is 1.15 mm, the width of the outward extension is 0.08 mm, and isosceles right triangles with a side length of 0.06 mm are cut off at the four corners.

8. A dual-polarization complementary millimeter wave antenna according to claim 1 or 6, characterized in that: A pair of parallel microstrip lines is provided at the connection between the trapezoidal dipole structure and the square ring structure, and the width of the microstrip lines is 0.08 mm and the length is 0.175 mm.

9. A dual-polarization complementary millimeter wave antenna according to claim 1 or 6, characterized in that: The length of the transverse groove of the H-shaped slot (13) is 1.1 mm, and the width is 0.2 mm. The length of the vertical grooves on both sides of the transverse groove is 0.9 mm, and the width is 0.3 mm.

10. The dual-polarization complementary millimeter wave antenna according to claim 2, characterized in that: The diameter of the short-circuit metal column (14) is not greater than λ0 / 10, and the distance between the centers of two adjacent short-circuit metal columns (14) is not greater than twice the diameter of the short-circuit metal column (14).

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