A high-gain beam frequency scanning antenna and a design method thereof

Abstract

The application discloses a high-gain beam frequency scanning antenna and a design method thereof, wherein a fan ring patch is arranged above a floor and serves as a dipole of the high-gain beam frequency scanning antenna, the fan ring patch is connected with the floor through a short-circuit wall, forms a non-enclosed structure with an inner circular arc short-circuit, an outer circular arc and a radial direction open circuit, and a feeding structure is arranged on the non-enclosed structure. The high-gain characteristic can be realized by changing the length of the characteristic dipole to be more than 1.5 times of a wavelength and changing the size of a dipole central angle. The three-mode resonance can be formed by adding branches and slots to the dipole and disturbing the high-order mode. Due to the excitation of the high-order mode, the maximum beam of the radiation pattern of the elevation plane is offset to the -x direction with the increase of the frequency, so that the function of the beam frequency scanning is obtained in the high frequency band.

Description

Technical Field

[0001] This invention relates to a design method for a high-gain beam frequency scanning antenna, belonging to the fields of wireless communication and microwave technology. Background Technology

[0002] With the continuous increase in mobile communication system services, communication equipment is constantly evolving towards miniaturization, placing increasingly higher demands on antenna size, integration, and gain. Because the gain of a single microstrip antenna is relatively low, a large number of elements are required for array formation, leading to a significant decrease in antenna efficiency due to the complexity and losses of the feeding network. Therefore, researching high-gain microstrip element antennas has significant practical value, as it can reduce the number of antenna elements, achieve antenna array miniaturization, and simplify the feeding network.

[0003] On the other hand, because future wireless communication systems integrate communication and sensing functions, antennas need to have both relatively stable beams and frequency scanning characteristics similar to leaky-wave antennas, with each fulfilling the communication and sensing functions respectively. Conventional antennas for integrated communication and sensing functions require array antennas or large leaky-wave antennas, which are both complex and costly. Summary of the Invention

[0004] To achieve high gain and beam scanning capabilities while minimizing the complexity of the antenna system, this invention proposes a high-gain beam frequency scanning antenna. By changing the length of the vibrator and adding stubs and slots to the vibrator, it can generate high end-fire gain on the low-to-mid frequency elevation plane while also achieving beam frequency scanning capabilities in the high-frequency band.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A design method for a high-gain beam frequency scanning antenna, the design method specifically comprising:

[0007] A fan-shaped patch is placed above the floor, and a medium is filled between the floor and the fan-shaped patch;

[0008] The inner arc edge of the fan-shaped patch is connected to the ground plane through the short-circuit wall, forming a non-closed structure with an inner arc short circuit and a straight edge and an outer arc open circuit, which serves as the main vibrator of the antenna.

[0009] The equivalent magnetic current formed by the electric field at the straight edge of the fan-shaped patch and the edge of the open-circuit end of the outer arc is used as the radiation source of the antenna.

[0010] A power supply structure is provided on the non-enclosed structure;

[0011] High gain of the patch antenna can be achieved by setting the outer arc length of the sector ring patch to be more than 1.5 times the wavelength, and by changing the ratio of the inner and outer diameters and the size of the central angle of the sector ring patch.

[0012] Furthermore, the floor is parallel to the fan-shaped patch, and the distance between the fan-shaped patch and the floor is no greater than 0.25 times the wavelength.

[0013] Furthermore, the relative permittivity of the medium is 1-100.

[0014] Furthermore, a mode perturbation device is provided on the non-enclosed structure to tune the resonant frequency.

[0015] Furthermore, the mode perturbation device is a combination of stubs and slots, which perturbs higher-order modes to form three-mode resonance, thereby obtaining the function of beam frequency scanning in the high-frequency band.

[0016] A high-gain beam frequency scanning antenna is fabricated using the method described above.

[0017] Compared with existing technologies, the present invention, employing the above technical solution, has the following technical advantages: The present invention achieves high gain characteristics by changing the length of the characteristic oscillator to more than 1.5 times the wavelength and by changing the size of the oscillator's central angle; by adding stubs and slots to the oscillator, higher-order modes can be disturbed to form a three-mode resonance. Due to the excitation of higher-order modes, the maximum beam of the radiation pattern on the elevation plane shifts towards the -x direction as the frequency increases, thereby achieving beam frequency scanning in the high-frequency band. This not only effectively reduces the antenna size, but also ensures that the radiation performance is independent of materials and can directly achieve high gain and beam frequency scanning using air as the dielectric. This facilitates a significant simplification of the antenna structure and manufacturing process, reducing costs and meeting the application needs of future wireless communication. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the front structure of the patch antenna;

[0019] Figure 2 This is a schematic diagram of the three-dimensional structure of the patch antenna;

[0020] Figure 3 The XZ plane radiation pattern of a patch antenna with a central angle of 210 degrees and an inner-outer diameter ratio of 1:3 is calculated using HFSS software at a frequency of 2.94 GHz.

[0021] Figure 4 The XZ plane radiation pattern of a patch antenna with a central angle of 210 degrees and an inner-outer diameter ratio of 1:3 is obtained by calculation and experimental measurement using HFSS software at frequencies of 2.66 GHz and 3.66 GHz.

[0022] The labels in the diagram are: 1 is a fan-shaped patch with rectangular slots and branches, 2 is the power supply structure, 3 is the rectangular slot, 4 is the branch, and 5 is the floor. Detailed Implementation

[0023] Embodiments of the present invention are described in detail below, examples of which are illustrated in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0024] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless defined as herein.

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings:

[0026] This invention proposes a novel design method for a high-gain beam frequency scanning antenna, such as... Figure 1 and 2 As shown, a fan-shaped patch is set above the floor to serve as the vibrator of the high-gain beam frequency scanning antenna. The inner arc of the fan-shaped patch is connected to the floor through a short-circuit wall, forming a non-closed structure with the inner arc short-circuited and the outer arc open in the straight edge direction, which serves as a radiation source. A feeding structure is set on the non-closed structure.

[0027] High-gain characteristics of patch antennas can be achieved by changing the length of the characteristic element to more than 1.5 times the wavelength and by changing the size of the element's central angle. Adding stubs and slots to the element can disturb higher-order modes to form a three-mode resonance. Due to the excitation of higher-order modes, the maximum beam of the radiation pattern on the elevation plane shifts towards the -x direction as the frequency increases, thus achieving beam frequency scanning in the high-frequency band. This antenna can be fabricated on a dielectric constant of 1-100, achieving end-fire gain of 11.5 dBi or higher with a single-element antenna. Single-element antennas offer a series of advantages, including high gain, small size, simple structure, low cost, and rigorous mathematical principles. This significantly simplifies the antenna structure and meets the application requirements of next-generation wireless communication.

[0028] In one embodiment, using air as the dielectric, the high-gain beamfrequency scanning antenna consists of a fan-shaped patch with two slots and branches symmetrical about the central axis of the fan-shaped ring and a ground plane. The central angle of the fan-shaped patch constituting the main oscillator is 210°, the radius of the outer arc is 47mm, the radius of the inner arc is 18mm, and the ratio of the inner to outer diameter is 1:3. The distance from the excitation point on the main oscillator to the center of the main oscillator is 39mm. The distance between the fan-shaped patch and the ground plane is 7mm. The two slots are symmetrical about the central axis of the fan-shaped ring and located at ±22° from the central axis, with a length of 17mm and a width of 7mm. The two branches are symmetrical about the central axis of the fan-shaped ring and located at ±70° from the central axis, with a length of 14.5mm and a width of 9mm. The ground plane is a rectangular patch with a length of 165mm and a width of 160mm. The XZ plane radiation pattern of the high-gain beamfrequency scanning antenna at 2.94GHz, obtained by simulation calculation using HFSS software and experimental measurement, is shown below. Figure 3 As shown, the solid line represents the principal polarization obtained from experimental measurements, the dashed line represents the principal polarization obtained from simulation calculations, θ = 0° (+z axis) is the end-fire direction, and the end-fire gain is 10.5 dBi.

[0029] The XZ-plane radiation patterns of the high-gain beam frequency scanning antenna at 2.66 GHz and 3.66 GHz, obtained by simulation calculation using HFSS software and experimental measurement, are shown below. Figure 4 As shown, where θ = 0° (+z axis) is the end-fire direction, the simulation calculation and experimental measurement results are in good agreement, proving the correctness and feasibility of the scheme.

[0030] By using the aforementioned three-mode resonant patch antenna with a central angle of 210° and a wavelength of 1.5 times, the end-fire enhancement characteristics of the unit patch antenna can be achieved under three-mode resonance conditions. Ultimately, a gain of 11.5 dBi or higher can be obtained in the end-fire direction perpendicular to the metal floor, as well as the function of 45° beam frequency scanning in the elevation radiation direction.

[0031] In summary, the design scheme of this invention not only reduces the antenna size, but also ensures that the radiation performance is independent of materials and can be achieved directly using air as the medium, which helps to reduce complexity and cost. The high-gain beam frequency scanning antenna designed in this invention has a series of advantages, including high gain of the elements, small size, simple structure and low cost, and rigorous mathematical principles.

[0032] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any transformations or substitutions that can be conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A design method for a high-gain beam frequency scanning antenna, characterized in that, The design method is specifically as follows: A fan-shaped patch (1) is placed above the floor (5), and a medium is filled between the floor (5) and the fan-shaped patch (1); The inner arc edge of the fan-shaped patch (1) is connected to the ground plane (5) through the short-circuit wall, forming a non-closed structure with an inner arc short circuit and a straight edge and an outer arc open circuit, which serves as the main vibrator of the antenna; The equivalent magnetic current formed by the electric field at the edge of the straight side of the fan-shaped patch (1) and the edge of the open circuit of the outer arc is used as the radiation source of the antenna. A power supply structure (2) is provided on the non-enclosed structure. By setting the outer arc length of the fan ring patch (1) to more than 1.5 times the wavelength, and by changing the ratio of the inner and outer diameters and the size of the central angle of the fan ring patch (1), the high gain of the patch antenna can be achieved. A mode disturbance device combining stubs (4) and slots (3) is set on the non-closed structure to disturb the higher-order modes to form a three-mode resonance, thereby obtaining the function of beam frequency scanning in the high-frequency band.

2. The design method of a high-gain beam frequency scanning antenna according to claim 1, characterized in that, The floor (5) is parallel to the fan-shaped patch (1), and the distance between the fan-shaped patch (1) and the floor (5) is no more than 0.25 times the wavelength.

3. The design method of a high-gain beam frequency scanning antenna according to claim 1, characterized in that, The relative permittivity of the medium is 1-100.

4. A high-gain beam frequency scanning antenna, characterized in that, It is prepared by the method described in any one of claims 1 to 3.

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