阅读说明：本技术 一种圆极化定频波束扫描漏波天线 (Circular polarization fixed frequency beam scanning leaky-wave antenna ) 是由 孟繁义 韩剑桥 顾晓峰 于 2021-06-28 设计创作，主要内容包括：本发明公开了一种圆极化定频波束扫描漏波天线,属于微波天线工程技术领域。本发明通过在不同寄生带条与金属地板层之间加载正向或反向的直流偏置电压,实现对两个PIN二极管开关状态的分别控制,为了保证圆极化辐射单元的圆极化特性,两个PIN二极管开关状态要保持相同(同时为导通或者同时为断开),当直流偏置电压控制两个PIN二极管在“导通”和“断开”两种状态间切换时,圆极化辐射单元的工作频率发生变化,实现偏置电压对圆极化辐射单元辐射电磁波的调控效果,继而获得一种具有低剖面,低成本,波束扫描,圆极化的定频波束扫描漏波天线。(The invention discloses a circularly polarized fixed-frequency beam scanning leaky-wave antenna, and belongs to the technical field of microwave antenna engineering. According to the invention, forward or reverse direct current bias voltages are loaded between different parasitic strips and a metal floor layer to respectively control the switch states of the two PIN diodes, in order to ensure the circular polarization characteristic of the circular polarization radiation unit, the switch states of the two PIN diodes are kept the same (simultaneously on or simultaneously off), when the direct current bias voltages control the two PIN diodes to be switched between the two states of 'on' and 'off', the working frequency of the circular polarization radiation unit is changed, the regulation and control effect of the bias voltages on the radiation electromagnetic waves of the circular polarization radiation unit is realized, and then the fixed-frequency beam scanning leaky-wave antenna with low section, low cost, beam scanning and circular polarization is obtained.)

1. The circularly polarized fixed-frequency beam scanning leaky-wave antenna is characterized by comprising a metal radiation layer (1), an upper-layer dielectric substrate (2), a metal floor layer (3), a dielectric substrate bonding layer (4), a lower-layer dielectric substrate (5) and a metal feed layer (6) from top to bottom, wherein the metal radiation layer (1) and the metal floor layer (3) are respectively positioned on the upper surface and the lower surface of the upper-layer dielectric substrate (2); the upper dielectric substrate (2) and the lower dielectric substrate (5) are bonded through a dielectric substrate bonding layer (4); the metal feed layer (6) is positioned on the lower surface of the lower-layer dielectric substrate (5), and the metal floor layer (3) is of a hollow structure;

the length direction of the upper layer medium substrate (2) is the y-axis direction, the width direction is the x-axis direction, and the height direction is the z-axis direction;

metal radiation layer (1) including two rows of circular polarization radiating element (8), every row circular polarization radiating element (8) distribute at the upper surface equidistance of upper dielectric substrate (2) along the y axle direction, circular polarization radiating element (8) of adjacent row are crisscross or just to arranging, every circular polarization radiating element (8) all have 1 feed point for its feed, feed metal probe (7) pass lower floor's dielectric substrate (5) in proper order, dielectric substrate bond line (4), the hollow out construction and upper dielectric substrate (2) connection metal radiation layer (1) and metal feed layer (6) of metal floor layer (3).

2. The leaky-wave antenna with circularly polarized fixed-frequency beam scanning as claimed in claim 1, wherein said circularly polarized radiating element (8) comprises a circularly polarized patch (9), two parasitic strips (10) and two ground vias (13);

the circularly polarized patch (9) is a square corner cut patch with 4C-shaped hollow structures (11), the side length of the square is p, two corners are opposite angles, and the side length of the corner cut is t_bThe base angle is an isosceles right triangle of 45 degrees; the feed point is positioned on the circularly polarized patch (9) and has a center distance f from the circularly polarized patch (9)_x；

Two parasitic strips (10) are respectively positioned at the outer sides of two adjacent sides of the circularly polarized patch (9), and the width of each parasitic strip (10) is w₁Length of c_pEach parasitic strip (10) is spaced from the circularly polarized patch (9) by a distance p_sThe two parasitic strips (10) are respectively connected with the metal floor layer (3) through PIN diodes (12) and grounding through holes (13).

3. The leaky-wave antenna for circularly polarized fixed-frequency beam scanning as claimed in claim 2, wherein the 4C-shaped hollow structures (11) have the same size, and the length of the long arm of the C-shaped hollow structure (11) is l₁The length of the short arm is l₂The width of the gap is w_sAnd 4C-shaped hollow structures (11) are distributed in central symmetry, and the placing angles of the adjacent C-shaped hollow structures (11) are different by 90 degrees.

4. A circularly polarized fixed frequency beam scanning leaky-wave antenna according to claim 3, wherein the distance between adjacent circularly polarized radiating elements (8) in the same row is d₁The staggered distance between the circularly polarized radiation units (8) of different rows is d₂(ii) a The circularly polarized radiation units (8) of different rows are distributed in a mirror image mode.

5. The leaky-wave antenna with circularly polarized fixed-frequency beam scanning as claimed in claim 4, wherein the parameter range of the metal radiation layer (1) is as follows:

0.15λ₀≤d₁≤0.50λ₀、0≤d₂≤0.25λ₀、0.1λ₀≤p≤0.35λ₀、0.01λ₀≤t_b≤0.05λ₀、0.02λ₀≤l₁≤0.14λ₀、0≤l₂≤0.10λ₀、0.003λ₀≤w_s≤0.06λ₀、0.005λ₀≤f_x≤0.3λ₀、0.01λ₀≤w₁≤0.08λ₀、0.05λ₀≤c_p≤0.4λ₀and 0.003 lambda₀≤p_s≤0.05λ₀Wherein λ is₀Is the free space wavelength.

6. The leaky-wave antenna with circularly polarized fixed-frequency beam scanning as claimed in claim 5, wherein the metal feed layer (6) comprises a microstrip transmission line (16) and feed branches (17), the feed branches (17) are located on both sides of the microstrip transmission line (16) and are distributed in a staggered manner, one end of the feed branch (17) is connected to the feed point, and the other end of the feed branch (17) is connected to the microstrip transmission line (16).

7. The leaky-wave antenna with circularly polarized fixed-frequency beam scanning as claimed in claim 6, wherein the feeding point of the metal radiating layer (1) is opposite to the feeding point of the metal feeding layer (6), and the feeding point of the circularly polarized radiating element (8) is connected to the feeding point of the metal feeding layer (6) through a feeding metal probe (7).

8. The leaky-wave antenna with circularly polarized and fixed frequency beam scanning as claimed in claim 7, wherein the microstrip transmission line (16) has a width w₂The width of the feed branch (17) is w₃Length of l₃。

9. The leaky-wave antenna with circularly polarized fixed-frequency beam scanning as claimed in claim 8, wherein the parameter of the metal feed layer (6) has a range of values:

0.01λ₀≤w₂≤0.05λ₀，0.004λ₀≤w₃≤0.04λ₀，0.05λ₀≤l₃≤0.2λ₀wherein λ is₀Is the free space wavelength.

10. The leaky-wave antenna for circularly polarized fixed-frequency beam scanning according to claim 8, wherein the operating frequency band range of the antenna is more than 5.0GHz, and the specific parameter values are as follows:

d₁＝15mm，d₂＝7.5mm，p＝8.50mm，c_p＝1.00mm，t_b＝1.00mm，l₁＝3.00mm，l₂＝1.30mm，f_x＝2.00mm，w_s＝0.50mm，p_s＝0.15mm，w₁＝0.5mm，c_p＝6.00mm，w₂＝3.00mm，l₃＝5.30mm，w₃＝0.30mm；

the number of the circularly polarized radiation units (8) is 40, the thicknesses of the upper dielectric substrate (2) and the lower dielectric substrate (5) are both 1.27mm, and the dielectric constant is 6.15.

Technical Field

The invention relates to a circularly polarized fixed-frequency beam scanning leaky-wave antenna, and belongs to the technical field of microwave antenna engineering.

Background

The antenna is a key device in a wireless communication system, and the characteristics of the antenna directly determine the performance of the whole communication system. Modern communication systems have a strong demand for low profile, low cost, beam scanning antennas. Due to the advantages of rain attenuation resistance and multipath effect resistance, the circularly polarized wave has wide application prospects in communication in modern wireless mobile communication and satellite communication and various radar systems. Conventional phased array antennas have excellent beam scanning capabilities, but are equipped with a separate set of transmit/receive (T/R) components for each radiating element. The phased array is high in manufacturing cost due to the existence of a large number of T/R components, and meanwhile, the phased array antenna is large in size and heavy due to the complex heat dissipation structure, and the electromagnetic characteristics of the antenna are affected. Compared with a phased array antenna, the reflective array antenna and the transmissive array antenna do not need a complex power distribution network, use of a large number of T/R components is avoided, antenna cost is effectively reduced, but a certain distance needs to be kept between a feed horn and an antenna array surface in the antenna, so that the overall profile of the antenna is obviously improved, and the requirements of a modern communication system on low profile, miniaturization and integration of the antenna are difficult to meet.

The leaky-wave antenna is an antenna with the characteristics of simple structure, low profile and beam scanning. By loading some tunable devices, such as diodes, ferrite materials, liquid crystals and the like, in the leaky-wave antenna unit, fixed-frequency beam scanning can be conveniently realized. Therefore, the circularly polarized fixed-frequency beam scanning leaky-wave antenna with the advantages of miniaturization and low cost is provided, and the circularly polarized fixed-frequency beam scanning leaky-wave antenna has important significance for improving the overall performance level of modern wireless communication, radar and navigation systems.

Disclosure of Invention

The invention aims to provide a circularly polarized fixed-frequency beam scanning leaky-wave antenna which has the characteristics of low profile, low cost, beam scanning and circular polarization.

The technical scheme of the invention is as follows:

a circular polarization fixed frequency beam scanning leaky-wave antenna comprises a metal radiation layer 1, an upper dielectric substrate 2, a metal floor layer 3, a dielectric substrate bonding layer 4, a lower dielectric substrate 5 and a metal feed layer 6 from top to bottom, wherein the metal radiation layer 1 and the metal floor layer 3 are respectively positioned on the upper surface and the lower surface of the upper dielectric substrate 2; the upper dielectric substrate 2 and the lower dielectric substrate 5 are bonded into a whole through a dielectric substrate bonding layer 4; the metal feed layer 6 is positioned on the lower surface of the lower-layer dielectric substrate 5, and the metal floor layer 3 has a hollow structure to prevent the feed metal probe from forming a short circuit with the metal floor layer;

the length direction of the upper dielectric slab 2 is the y-axis direction, the width direction is the x-axis direction, and the height direction is the z-axis direction;

the metal radiation layer 1 is made of metal thin films and comprises two rows of circular polarization radiation units 8, each row of circular polarization radiation units 8 are equidistantly distributed on the upper surface of the upper-layer dielectric plate 2 along the y-axis direction, the circular polarization radiation units 8 in adjacent rows are staggered or oppositely arranged, each circular polarization radiation unit 8 is provided with 1 feed point for feeding, and a feed metal probe 7 sequentially penetrates through the lower-layer dielectric substrate 5, the dielectric substrate adhesive layer 4, the hollow structure of the metal floor layer 3 and the upper-layer dielectric substrate 2 to be connected with the metal radiation layer 1 and the metal feed layer 6.

Further defined, the circularly polarized radiating element 8 comprises a circularly polarized patch 9, two parasitic strips 10 and two ground vias 13.

Further, the circularly polarized patch 9 is a square corner cut patch having 4C-shaped hollow structures 11, the side length of the square is p, two corners are opposite angles, and the corner cut is t_bThe base angle is an isosceles right triangle of 45 degrees and is used for realizing circularly polarized radiation; the feed point is located on the circularly polarized patch 9 and has a center distance f from the circularly polarized patch 9_x。

Further, two parasitic strips 10 are respectively arranged outside two adjacent sides of the circularly polarized patch 9, and each parasitic strip 10 is wideDegree w₁Length of c_pEach parasitic strip 10 is spaced from the circularly polarized patch 9 by a distance p_sThe two parasitic strips 10 are connected to the metal floor layer 3 by means of diodes and ground vias 13, respectively.

Further, the 4C-shaped hollow structures 11 have the same size, and the length of the long arm of the C-shaped hollow structure 11 is l₁The length of the short arm is l₂The width of the gap is w_sAnd 4C-shaped hollow structures 11 are distributed in a central symmetry manner, and the placing angles of the adjacent C-shaped hollow structures 11 are different by 90 degrees.

Further, the distance d between adjacent circularly polarized radiation units 8 in the same row is defined₁The staggered distance between the circularly polarized radiation units 8 of different rows is d₂(ii) a The circularly polarized radiation elements 8 in different rows are distributed in a mirror image manner.

Further, the parameter range of the metal radiation layer 1 is defined as follows:

0.15λ₀≤d₁≤0.50λ₀、0≤d₂≤0.25λ₀、0.1λ₀≤p≤0.35λ₀、0.01λ₀≤t_b≤0.05λ₀、0.02λ₀≤l₁≤0.14λ₀、0≤l₂≤0.10λ₀、0.003λ₀≤w_s≤0.06λ₀、0.005λ₀≤f_x≤0.3λ₀、0.01λ₀≤w₁≤0.08λ₀、0.05λ₀≤c_p≤0.4λ₀and 0.003 lambda₀≤p_s≤0.05λ₀Wherein λ is₀Is the free space wavelength.

Further, the metal feed layer 6 includes a microstrip transmission line 16 and feed branches 17, the feed branches 17 are located on both sides of the microstrip transmission line 16 and distributed in a staggered manner, one end of the feed branch 17 is connected to the feed point, and the other end of the feed branch 17 is connected to the microstrip transmission line 16.

Further, it is defined that a feeding point of the metal radiation layer 1 is opposite to a feeding point of the metal feeding layer 6, and a feeding point of the circularly polarized radiation unit 8 is connected to the feeding point of the metal feeding layer 6 through a feeding metal probe 7.

Further defined, the microstrip transmission line 16 has a width w₂The width of the feed branch 17 is w₃Length of l₃。

Further, the parameter range of the metal feed layer 6 is defined as follows:

0.01λ₀≤w₂≤0.05λ₀，0.004λ₀≤w₃≤0.04λ₀，0.05λ₀≤l₃≤0.2λ₀wherein λ is₀Is the free space wavelength.

Further limiting, the antenna operating frequency band range is above 5.0GHz, and the specific parameter values are as follows:

d₁＝15mm，d₂＝7.5mm，p＝8.50mm，c_p＝1.00mm，t_b＝1.00mm，l₁＝3.00mm，l₂＝1.30mm，f_x＝2.00mm，w_s＝0.50mm，p_s＝0.15mm，w₁＝0.5mm，c_p＝6.00mm，w₂＝3.00mm，l₃＝5.30mm，w₃＝0.30mm；

the number of the circularly polarized radiation units 8 is 40, the thicknesses of the upper dielectric substrate 2 and the lower dielectric substrate 5 are both 1.27mm, and the dielectric constant is 6.15.

The invention has the following beneficial effects: the circularly polarized fixed-frequency beam scanning leaky-wave antenna provided by the invention obtains the fixed-frequency beam scanning capability by regulating and controlling the radiation energy of each radiation unit. Specifically, forward or reverse direct current bias voltages are loaded between different parasitic strips and a metal floor layer to respectively control the switch states of the two PIN diodes, in order to ensure the circular polarization characteristic of the circular polarization radiation unit, the switch states of the two PIN diodes are kept the same (simultaneously on or simultaneously off), when the two PIN diodes are controlled to be switched between the two states of 'on' and 'off' by the direct current bias voltages, the working frequency of the circular polarization radiation unit changes, and the change of the working frequency means that the size and the phase of electromagnetic waves radiated by the circular polarization radiation unit change, namely the regulation and control effect of the bias voltages on the electromagnetic waves radiated by the circular polarization radiation unit is realized. In addition, the invention also has the following advantages:

(1) by utilizing the regulation and control characteristics of the circularly polarized radiation unit for radiating electromagnetic waves and combining a proper electromagnetic beam synthesis algorithm and a corresponding bias voltage control circuit, the electromagnetic beam scanning or electromagnetic beam forming of the whole circularly polarized fixed-frequency beam scanning leaky-wave antenna can be realized;

(2) the invention adopts the serial feed network, thus compared with the phased array, the invention has the advantages of low section surface, miniaturization and high integration level;

(3) the antenna provided by the invention does not need any TR component or TR chip, can realize beam scanning by only needing a simple diode, and has the advantage of low cost.

Drawings

Fig. 1 is a schematic three-dimensional structure diagram of a circular polarization fixed-frequency beam scanning leaky-wave antenna provided by the present invention;

FIG. 2 is a schematic structural diagram of a metal radiation layer;

FIG. 3 is an enlarged schematic view of the circularly polarized radiating element of FIG. 2;

FIG. 4 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 5 is a schematic diagram of a metal feed layer structure;

FIG. 6 is the far field pattern simulation result of the antenna of example 1 at 5.0 GHz;

in the figure, 1-a metal radiation layer, 2-an upper dielectric substrate, 3-a metal floor layer, 4-a substrate bonding layer, 5-a lower dielectric substrate, 6-a metal feed layer, 7-a feed metal probe, 8-a circular polarization radiation unit, 9-a circular polarization patch, 10-a parasitic strip, 11-a C-shaped hollow structure, 12-a PIN diode, 13-a grounding via hole, 14-a feed point, 15-a hollow structure of the metal floor layer, 16-a microstrip transmission line and 17-a feed branch node.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

The experimental procedures used in the following examples are conventional unless otherwise specified. The materials, reagents, methods and apparatus used, unless otherwise specified, are conventional in the art and are commercially available to those skilled in the art.

Example 1:

as shown in fig. 1 and 4, the circular polarization fixed-frequency beam scanning leaky-wave antenna comprises, from top to bottom, a metal radiation layer 1, an upper dielectric substrate 2, a metal floor layer 3, a dielectric substrate adhesive layer 4, a lower dielectric substrate 5 and a metal feed layer 6, wherein the metal radiation layer 1 and the metal floor layer 3 are respectively located on the upper surface and the lower surface of the upper dielectric substrate 2; the upper dielectric substrate 2 and the lower dielectric substrate 5 are bonded through a dielectric substrate bonding layer 4; the metal feed layer 6 is positioned on the lower surface of the lower-layer dielectric substrate 5, and the metal floor layer 3 has a hollow structure.

As shown in fig. 2, the metal radiation layer 1 includes two rows of circularly polarized radiation units 8, each row of circularly polarized radiation units 8 is equidistantly distributed on the upper surface of the upper dielectric plate 2 along the y-axis direction, the circularly polarized radiation units 8 in adjacent rows are staggered or aligned, each circularly polarized radiation unit 8 has 1 feeding point for feeding, and the feeding metal probe 7 sequentially passes through the lower dielectric substrate 5, the dielectric substrate adhesive layer 4, the hollow structure of the metal floor layer 3 and the upper dielectric substrate 2 to connect the metal radiation layer 1 and the metal feeding layer 6; the distance between the adjacent circularly polarized radiation units 8 in the same row is d₁The staggered distance between the circularly polarized radiation units 8 of different rows is d₂(ii) a The circularly polarized radiation elements 8 in different rows are distributed in a mirror image manner.

As shown in fig. 3, the circularly polarized radiating element 8 includes a circularly polarized patch 9, two parasitic strips 10, and two ground vias 13; the circularly polarized patch 9 is a square corner cut patch with 4C-shaped hollow structures 11, the side length of the square is p, the two corners are opposite angles, and the corner cut is t_bThe base angle is an isosceles right triangle of 45 degrees; the feed point is located on the circularly polarized patch 9 and has a center distance f from the circularly polarized patch 9_x(ii) a Two parasitic strips 10 are respectively arranged at the outer sides of two adjacent sides of the circularly polarized patch 9, and each parasitic strip is provided with a plurality of slots10 width of w₁Length of c_pEach parasitic strip 10 is spaced from the circularly polarized patch 9 by a distance p_sThe two parasitic strips 10 are connected to the metal floor layer 3 through PIN diodes 12 and ground vias 13, respectively. The 4C-shaped hollow structures 11 have the same size, and the length of the long arm of the C-shaped hollow structure 11 is l₁The length of the short arm is l₂The width of the gap is w_s(ii) a 4C type hollow out construction 11 are central symmetry and distribute, and the angle of putting of adjacent C type hollow out construction 11 differs 90, and 4C type hollow out construction 11 can take place electromagnetic resonance on the frequency that is lower for circular polarization paster to realize the miniaturized purpose of antenna.

As shown in fig. 5, the metal feed layer 6 includes a microstrip transmission line 16 and feed branches 17, the feed branches 17 are located at two sides of the microstrip transmission line 16 and are distributed in a staggered manner, one end of the feed branch 17 is connected with a feed point, and the other end of the feed branch 17 is connected with the microstrip transmission line 16; the feed point of the metal radiation layer 1 is opposite to the feed point of the metal feed layer 6, and the feed point of the circularly polarized radiation unit 8 is connected with the feed point of the metal feed layer 6 through a feed metal probe 7; the microstrip transmission line 16 has a width w₂The width of the feed branch 17 is w₃Length of l₃。

The structural parameters of the circularly polarized fixed-frequency beam scanning leaky-wave antenna are set as follows:

p＝8.50mm、c_p＝1.00mm、t_b＝1.00mm、l₁＝3.00mm、l₂＝1.30mm、f_x＝2.00mm、w_s＝0.50mm、p_s＝0.15mm、w₁＝0.5mm、c_p＝6.00mm；w₂＝3.00mm、l₃＝5.30mm、w₃＝0.30mm；

spacing d between circularly polarized radiating elements in the same row₁15mm, the pitch d of the unit staggers in different rows₂7.5mm, the number of the circularly polarized radiation units is 8 and 40;

the thicknesses of the upper dielectric substrate 2 and the lower dielectric substrate 5 are both 1.27mm, and the dielectric constant is 6.15.

The simulation result of the far-field directional pattern of the circularly polarized fixed-frequency beam scanning leaky-wave antenna at 5.0GHz is shown in FIG. 6, and the simulation result of the radiation characteristic parameters at 5.0GHz is shown in Table 1.

Table 15.0 GHz radiation characteristic parameter simulation results

As can be seen from fig. 6 and table 1, the leaky-wave antenna with circularly polarized fixed-frequency beams can realize ± 60 ° scanning at 5.0GHz, and can realize good circularly polarized radiation characteristics in the scanning range of-40 ° to +50 °, and the axial ratio is less than 3 dB. The peak gain of the array is 12.0dBic and the minimum gain is 9.9dBic, i.e. the antenna array shows good circular polarized beam scanning characteristics.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.