CN116073132A

CN116073132A - Single-layer patch broadband low-profile double-circular polarization millimeter wave reflective array antenna

Info

Publication number: CN116073132A
Application number: CN202211090312.7A
Authority: CN
Inventors: 代喜望; 张宇辉; 胡文浩; 付杨辉; 金华燕; 罗国清
Original assignee: Hangzhou Dianzi University
Current assignee: Hangzhou Dianzi University
Priority date: 2022-09-07
Filing date: 2022-09-07
Publication date: 2023-05-05

Abstract

The invention discloses a single-layer patch broadband low-profile double-circular polarization millimeter wave reflection array antenna which is divided into a feed source horn antenna (1) and a reflection plane (2). The reflection plane (2) is formed by a plurality of double circular polarization reflection units (3). The double circular polarization reflecting unit (3) comprises a metal microstrip functional layer (31), a dielectric substrate (32) and a metal reflecting bottom plate (33) which are designed based on a multi-resonant structure. The single-layer patch broadband low-profile double-circular polarization millimeter wave reflective array antenna realizes independent regulation and control of the phase of the left-hand circular polarization wave and the phase of the right-hand circular polarization wave of the Ka band through the combined action of the dynamic phase and the rotary phase, has the characteristics of broadband, low profile, high directivity and the like, and has wide application prospects in long-distance communication systems such as wireless communication, radar, remote sensing systems, satellite communication and the like.

Description

Single-layer patch broadband low-profile double-circular polarization millimeter wave reflective array antenna

Technical Field

The invention relates to the field of wireless communication electronic devices, in particular to a single-layer patch broadband low-profile double-circular polarization millimeter wave reflective array antenna.

Background

The high gain antennas such as the reflector antenna, the lens antenna, the phased array antenna and the like can be well applied to a long-distance communication system. Microstrip reflective array antennas combine the advantages of printed antennas, reflective surface antennas, and phased array antennas. Compared with the traditional reflecting surface antenna and lens antenna, the microstrip reflecting array antenna has smaller volume, lower section, lower manufacturing cost and lighter weight; compared with a phased array antenna, the microstrip reflection array antenna does not need to design a complicated feed network, and higher working efficiency is obtained in a space feed mode. Compared with a dual-polarized antenna, the single-polarized antenna is easier to be influenced by multipath fading in the signal transmission process, and the number of units after the array is also more than that of the dual-polarized antenna. In a long-distance transmission system, the matching between circularly polarized antennas is simpler than that of a linearly polarized antenna, the data transmission can be realized only by meeting the condition that the rotation directions are the same, and the linearly polarized antennas can be matched only by meeting a certain planning angle. Moreover, compared with the linear polarized wave, the circular polarized wave has stronger anti-interference capability, and the linear polarized wave is easy to be mismatched due to the change of the polarization angle in the transmission process. The single-layer patch broadband low-profile double-circular polarization millimeter wave antenna has the advantages of high directivity, high gain, wide working bandwidth, low profile, low cost and the like, and can be well applied to a long-distance communication system.

At present, the implementation of the dual circularly polarized reflective array mainly comprises the following modes: 1. generating left-hand/right-hand circularly polarized waves by using a left-hand/right-hand circularly polarized feed source, and forming left-hand/right-hand circularly polarized directional beams by a left-hand/right-hand circularly polarized wave reflecting layer regulated and controlled by a dynamic phase; 2. converting the circularly polarized wave generated by the feed source into two linearly polarized waves through the circular polarizer, reflecting the two linearly polarized waves back to the circular polarizer through the polarized reflecting layer, and synthesizing the circularly polarized waves again; 3. meanwhile, a rotatable anisotropic unit is utilized to form a double circular polarization reflecting layer by utilizing a dynamic phase and a geometric phase, and the arbitrary phase delay regulation and control of the left-hand/right-hand circular polarization wave can be realized by using only one functional layer. The third method can realize the design of the dual circular polarization reflection array by only one functional layer, so that compared with the first two methods, the designed reflection array antenna has the advantages of lower section, lower cost, higher reflection efficiency and the like. In the existing related designs at home and abroad, the bandwidth of the dual circular polarization reflection array is generally narrower, and the unit design for realizing the independent regulation and control of dual circular polarization waves by adopting a single functional layer is more complex, the manufacturing difficulty is higher, and the cost is more difficult to control.

Disclosure of Invention

According to the defects of the prior art, the invention provides the single-layer patch broadband low-profile double-circular polarization millimeter wave reflection array antenna, which realizes independent regulation and control of the phase of the left-hand circular polarization wave and the phase of the right-hand circular polarization wave of a Ka wave band through the combined action of a dynamic phase and a rotary phase and has the characteristics of wide band, low profile, high directivity and the like. The reflection plane functional layer is designed by only one layer of patch, the minimum line width is controlled to be 0.2mm, and the reflection plane functional layer can be manufactured by adopting a printed circuit process, thereby being convenient for large-scale mass production and effectively reducing the production cost.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a single-layer patch broadband low-profile dual-circularly polarized millimeter wave reflective array antenna comprises a reflective plane and a dual-circularly polarized horn antenna for space feeding.

Preferably, the reflection plane is formed by periodically arranging 1013 double circularly polarized reflection units, and the number of the units at the maximum diameter is 35.

Preferably, the dual circularly polarized reflection unit is composed of a metal microstrip functional layer based on a multi-resonant structure design, a dielectric substrate and a metal reflection bottom plate.

Preferably, the metal microstrip functional layer is formed by combining a first fan-shaped microstrip line, a second fan-shaped microstrip line, a first rectangular microstrip line, a second rectangular microstrip line, a third rectangular microstrip line, a first arc-shaped microstrip line and a second arc-shaped microstrip line. The first fan-shaped microstrip line is connected with the first arc-shaped microstrip line through a first rectangular microstrip line, and the second fan-shaped microstrip line is connected with the second arc-shaped microstrip line through a second rectangular microstrip line.

The metal microstrip functional layer is printed on a dielectric substrate with the thickness of 0.762mm, the dielectric constant of 2.2 and the loss tangent of 0.0009.

The distance between the metal reflecting structure and the metal reflecting bottom plate is 1.8mm, and an air layer of 1.038mm is arranged between the dielectric substrate and the metal reflecting bottom plate.

Preferably, the dual circular polarization horn antenna is located right above the reflection plane, the distance between the aperture center of the dual circular polarization horn antenna and the geometric center of the reflection plane is F, the diameter of the reflection plane is D, and the value of F/D is between 0.8 and 1.2 to ensure the antenna efficiency.

The invention has the following characteristics and beneficial effects:

by adopting the technical scheme, the first double-circular polarization reflecting unit designed based on the multi-resonance structure has about 61% of impedance bandwidth, which is far greater than the bandwidth of the existing double-circular polarization reflecting array antenna unit. In the metal microstrip functional layer of the double circular polarization reflection unit, a first sector microstrip line, a second sector microstrip line, a first rectangular microstrip line, a second rectangular microstrip line, a third rectangular microstrip line, a first arc microstrip line and a second arc microstrip line jointly act to introduce four resonance points in a frequency band, and the four resonance points jointly act to widen the impedance bandwidth of the unit to a certain extent;

and the linear polarization reflection phase of the reflection unit can be adjusted by adjusting the sizes of the first sector microstrip line, the second sector microstrip line and the third rectangular microstrip line, so that the phase difference of two axes reaches 180 degrees. The lengths of the first arc-shaped microstrip line and the second arc-shaped microstrip line can be adjusted to dynamically adjust the reflection phase, so that the reflection phase covers 0-180 degrees to form a first group of reflection units. The first group of reflecting units are rotated by 90 degrees, so that the reflecting phase covers 180-360 degrees, and the second group of reflecting units are formed. The first group of reflecting units and the second group of reflecting units form all reflecting units, and all phases of 0-360 degrees can be covered. The rotation phase can be adjusted by rotating the double-circular polarization reflection unit, so that the phase difference of the left-hand circular polarization and the right-hand circular polarization is increased from 0 degrees to 360 degrees, the relation between the rotation angle rotation and the phase difference is 1:4, namely, the unit rotates by 1 degree, and the phase difference of the left-hand circular polarization wave and the right-hand circular polarization wave is increased by 4 degrees. In a comprehensive way, the lengths of the first arc-shaped microstrip line and the second arc-shaped microstrip line and the unit rotation angle rotation are adjusted simultaneously, so that the reflection phases of the left-hand circularly polarized wave and the right-hand circularly polarized wave can be regulated and controlled independently by the single functional layer, and the single functional layer has lower cross polarization;

the invention has simple structure, only one patch structure, the minimum line width is 0.2mm, the section height is only 1.8mm, the invention can be manufactured by adopting a printed circuit process, has low cost, easy assembly and convenient use, and can be better applied to long-distance communication systems such as wireless communication, radars, remote sensing systems and the like.

Drawings

In order to more clearly illustrate the embodiments of the invention or the technical solutions of the prior art, the drawings which are used in the description of the embodiments or the prior art will be briefly described, it being obvious that the drawings in the description below are only some embodiments of the invention, and that other drawings can be obtained according to these drawings without inventive faculty for a person skilled in the art.

FIG. 1 is a schematic three-dimensional structure of an embodiment of the present invention;

FIG. 2 is a schematic three-dimensional structure and a schematic planar structure of a dual circularly polarized reflection unit according to an embodiment of the present invention;

FIG. 3 is a schematic plan view of the dual circularly polarized reflection unit 1 to the dual circularly polarized reflection unit 18 according to the embodiment of the present invention;

FIG. 4 is a schematic plan view of the dual circularly polarized reflection units 19 to 36 according to the embodiment of the present invention;

FIG. 5 is a graph showing the variation of the reflection coefficient of right-hand circularly polarized wave with frequency of the double circularly polarized reflection units 1 to 18 according to the embodiment of the present invention;

FIG. 6 is a graph showing the variation of the reflection coefficient of the left-hand circularly polarized wave with frequency of the double circularly polarized reflection units 1 to 18 according to the embodiment of the present invention;

FIG. 7 is a graph showing the variation of the degree of separation between the left-hand circularly polarized wave and the right-hand circularly polarized wave of the double circularly polarized reflection units 1 to 18 according to the embodiment of the present invention;

fig. 8 shows normalized gains obtained by simulating a right-hand circularly polarized reflected wave (rhcp_r) and a left-hand circularly polarized reflected wave (rhcp_l) of a right-hand circularly polarized horn spatial feed, and a left-hand circularly polarized reflected wave (lhcp_l) and a right-hand circularly polarized reflected wave (lhcp_r) of a left-hand circularly polarized horn spatial feed, respectively, in the phi=0° (yoz plane) direction at 30 GHz.

In the figure: 1. a dual circularly polarized horn antenna; 2. a reflection plane; 3. a double circularly polarized reflection unit; 31. gold metal microstrip functional layer; 32. a dielectric substrate; 33. a metal reflective backplane; 41. a first arc-shaped microstrip line; 42. a first rectangular microstrip line; 43. a first sector microstrip line; 44. a third rectangular microstrip line; 45. a second sector microstrip line; 46. a second rectangular microstrip line; 47. and a second arc microstrip line.

Detailed Description

The invention provides a single-layer patch broadband low-profile double-circular polarization millimeter wave reflection array antenna, which comprises a double-circular polarization horn antenna and a reflection plane. The reflection plane is composed of a plurality of double circularly polarized reflection units. The single-layer patch broadband low-profile double-circular polarization millimeter wave reflection array antenna provided by the invention can generate independent left-hand circular polarization and right-hand circular polarization high-directivity beams in the frequency range of 19.64 GHz-36.89 GHz. The reflection plane has a cross-sectional height of 1.8mm and 0.18 wavelength at 30 GHz. Compared with the existing double circularly polarized reflective array antenna, the invention has wider working bandwidth. Simulation results show that the single-layer patch broadband low-profile double-circular polarization millimeter wave reflection array antenna provided by the invention has good performance in the frequency band of 19.64 GHz-36.89 GHz, and can be better applied to long-distance communication systems such as wireless communication, radars, remote sensing systems and the like.

The invention is further described below with reference to the accompanying drawings.

As shown in fig. 1, the invention provides a single-layer patch broadband low-profile double-circular polarization millimeter wave reflection array antenna, which comprises a double-circular polarization horn antenna 1 and a reflection plane 2. The dual circular polarization horn antenna 1 is positioned right above the reflection plane 2, and the distance between the caliber center of the dual circular polarization horn antenna 1 and the geometric center of the reflection plane 2 is F. For ease of calculation, in the present example, f=150 mm is taken, 15 wavelengths at 30 GHz. The diameter of the reflection plane 2 is D, and for convenience of fixing, the dielectric substrate is square, and the side length is D, and in the example of the present invention, d=4.6 mm×35=161 mm, and at 30GHz, 16.1 wavelengths are taken.

The reflection plane 2 is formed by a double circularly polarized reflection unit 3, the three-dimensional structure of which is given by fig. 2. The double circular polarization reflecting unit is composed of a gold metal microstrip functional layer 31, a dielectric substrate 32 and a metal reflecting bottom plate 33. The dielectric substrate 32 has a thickness of 0.762mm, a dielectric constant of 2.2 at 30GHz of 0.762 wavelength, and a loss tangent of 0.0009. An air layer with the thickness of 1.038mm is arranged between the dielectric substrate 32 and the metal reflection bottom plate 33, and the bandwidth of the double circular polarization reflection unit 3 can be increased on the basis of not changing the thickness of the dielectric substrate 32 by introducing the air layer.

The planar structure diagram of the metal microstrip functional layer 31 is given in fig. 2, and includes a first arc microstrip line 41, a first rectangular microstrip line 42, a first sector microstrip line 43, a third rectangular microstrip line 44, a second sector microstrip line 45, a second rectangular microstrip line 46, and a second arc microstrip line 47. The first arc-shaped microstrip line 41 is connected with the first sector-shaped microstrip line 43 through a first rectangular microstrip line 42, the second arc-shaped microstrip line 47 is connected with the second sector-shaped microstrip line 45 through a second rectangular microstrip line 46, and the first sector-shaped microstrip line 43 is connected with the second sector-shaped microstrip line 45 through a third rectangular microstrip line 44.

The first arc-shaped microstrip line 41, the first rectangular microstrip line 42, the first sector-shaped microstrip line 43, the third rectangular microstrip line 44, the second sector-shaped microstrip line 45, the second rectangular microstrip line 46, and the second arc-shaped microstrip line 47 cooperate to introduce 4 resonance points in the frequency band. By changing the lengths of the first and second

arcuate microstrip lines

41 and 47, respectively, the angles of the first and second

sectorial microstrip lines

43 and 45, respectively, and the lengths of the third rectangular microstrip line 44 may be adjusted to the above-mentioned 4 resonance points, respectively, so that the dynamic phase is changed from 0 ° to 180 °. The planar structure of the cell formed with a gradient of 10 ° is given in fig. 3. The cells in fig. 3 are rotated 90 deg. to obtain a second set of cells, respectively, as shown in fig. 4, with dynamic phase variation in the range of 180 deg. to 360 deg..

The reflection coefficient of the left-hand circularly polarized wave of the double circularly polarized reflection unit in fig. 3 is given by fig. 5, the reflection coefficient of the right-hand circularly polarized wave is given by fig. 6, and the reflection coefficients of 18 units between 19.64GHz and 36.89GHz are all larger than-0.5 dB. Illustrating that the dual circularly polarized reflection unit of fig. 3 can maintain high reflectivity in the 19.64 GHz-36.89 GHz band.

The isolation between the left-hand circularly polarized wave and the right-hand circularly polarized wave of the double circularly polarized reflection unit in fig. 3 is given by fig. 7, and the cross polarization isolation of 18 units between 19.64GHz and 36.89GHz is lower than 10dB.

Fig. 8 is a normalized gain pattern at yoz for a dual circularly polarized reflective array antenna at 30GHz spatial feed by a left hand circularly polarized horn antenna and a right hand circularly polarized horn antenna, respectively. When the left-hand horn is fed, the left-hand circularly polarized reflected wave points to theta= -20 degrees, cross polarization at the point is < -40dB, cross polarization at all frequency points is < -20dB, and the maximum gain is 30.90dBic. When the right-hand horn is fed, right-hand circularly polarized reflected waves point to theta=15°, cross polarization at the point is < -30dB, cross polarization at all frequency points is < -20dB, and the maximum gain is 31.16dBic.

Claims

1. A single-layer patch broadband low-profile double-circular polarization millimeter wave reflective array antenna is characterized in that: comprises a double circular polarization horn antenna (1) and a reflection plane (2);

the center of the caliber surface of the double circular polarization horn antenna (1) and the geometric center of the reflection plane (2) are positioned on the same coordinate axis;

the reflection plane (2) is fed by the double circular polarization horn antenna (1) in space, electromagnetic waves from the double circular polarization horn antenna (1) are reflected by the reflection plane (2) and form an equal phase surface after phase modulation, and a plurality of beams are overlapped to form a high-directivity double circular polarization beam.

2. The single-layer patch broadband low-profile dual circularly polarized millimeter wave reflective array antenna as claimed in claim 1, wherein the reflective plane (2) is formed by a plurality of dual circularly polarized reflective units (3) arranged periodically.

3. A single-layer patch broadband low-profile dual circularly polarized millimeter wave reflective array antenna according to claim 2, wherein each dual circularly polarized reflective unit (3) comprises: a metal microstrip functional layer (31), a dielectric substrate (32) and a metal reflection bottom plate (33); the metal microstrip functional layer (31) comprises: a first arc-shaped microstrip line (41), a first rectangular microstrip line (42), a first sector-shaped microstrip line (43), a third rectangular microstrip line (44), a second sector-shaped microstrip line (45), a second rectangular microstrip line (46) and a second arc-shaped microstrip line (47);

the metal microstrip functional layer (31) is a core part of the double circular polarization reflection unit (3), and incident waves are subjected to phase modulation through the metal microstrip functional layer (31): the phase difference between the two coordinate axis directions reaches 180 degrees, and the reflection phase of the synthesized left-hand/right-hand circularly polarized wave reaches the design requirement.

4. A single-layer patch broadband low-profile dual circularly polarized millimeter wave reflective array antenna according to claim 3, characterized in that the metallic microstrip functional layer (31) is printed on a dielectric substrate (32) with a thickness of 0.762mm, and an air layer of 1.038mm is present between the dielectric substrate (32) and the metallic reflective bottom plate (33).

5. A single-layer patch broadband low-profile dual circularly polarized millimeter wave reflective array antenna as claimed in claim 3, wherein the metallic microstrip functional layer (31) has a shape of a sector, a rectangle, an arc.

6. The single-layer patch broadband low-profile dual circularly polarized millimeter wave reflective array antenna according to claim 1, wherein the distance between the aperture center of the dual circularly polarized horn antenna (1) and the geometric center of the reflective plane (2) is F, and the diameter of the reflective plane (2) is D, wherein f=150 mm, and d=161 mm.