Circular antenna array and full-array antenna thereof

Abstract

The utility model relates to a circular antenna array and a full-array antenna thereof, belongs to the technical field of satellite communication ground terminal antennas, and solves the problems of how to improve the broadband of the antenna array and reduce mutual coupling among array antenna units. The radiation patch on the third base layer generates radiation, and the parasitic patch on the first base layer introduces a new resonance point, so that the working bandwidth of the antenna is expanded; impedance matching in the working frequency band of the antenna array is carried out by adjusting the thickness of the second base layer; a metal wall structure increases the isolation degree between antenna units, inhibits surface wave propagation, improves the mutual coupling strength between the units, and improves the active standing wave performance of antenna array scanning.

Description

Technical Field

[0001] The utility model belongs to the technical field of satellite communication ground terminal antennas, and relates to a circular antenna array and a full-array antenna thereof. Background Art

[0002] Common ground terminal antennas for satellite communication include parabolic antennas, antenna arrays, and phased array antennas. Traditional parabolic antennas and antenna arrays use mechanical servo systems to track satellites, with large inertia, slow speed, and high profile. The terminal antenna in the form of a phased array is an antenna that changes the pattern pointing by controlling the feeding phase of the radiation units in the antenna. It has a fast response and a low profile. The phased array antenna is the development trend of terminal antennas in the satellite industry. For a two-dimensional phased array antenna, in order to achieve wideband wide-angle scanning, it is not only necessary to reduce the active standing wave ratio within the antenna scanning range, but also necessary to reduce the size between antenna elements. When the antenna element spacing is smaller, the mutual coupling between antenna elements intensifies, which will deteriorate the active standing wave of the antenna. If the antenna element spacing is too large, when the antenna scans to a large angle, large grating lobes will appear within the visible range. The satellite communication industry has an access standard for the pattern of terminal antennas, and the appearance of grating lobes is likely to interfere with other satellites. Therefore, in order to meet wide-angle scanning, the antenna element spacing must be reduced. After the spacing is reduced, the mutual coupling between elements increases, and it is necessary to reduce the active standing wave ratio within the antenna scanning range. Summary of the Utility Model

[0003] The technical solution of the utility model is used to solve the problem of how to improve the broadband of the antenna array and reduce the mutual coupling between the array antenna elements.

[0004] The utility model solves the above technical problems through the following technical solutions:

[0005] A circular antenna array, comprising: a top layer structure (10), a middle layer structure (20), and a bottom layer structure (30). The top layer structure (10), the middle layer structure (20), and the bottom layer structure (30) are aligned and pressed together in the order from top to bottom. On the upper surface of the first base layer (101) of the top layer structure (10), six regular hexagon microstrip coils (102) are laid. The six regular hexagon microstrip coils (102) are rotationally connected at 360° with the center of the first base layer (101) as the center to form a closed array with seven regular hexagon antenna array units. Each pair of the six regular hexagon microstrip coils (102) shares one side. Seven parasitic patches (103) are respectively laid at the centers of the six regular hexagon microstrip coils (102) and the center of the closed array. On the upper surface of the third base layer (301) of the bottom layer structure (30), a closed array identical to that on the upper surface of the first base layer (101) and composed of six regular hexagon microstrip coils (102) is laid. The projection of the closed array on the upper surface of the third base layer (301) coincides with the projection of the closed array on the upper surface of the first base layer (101) in a top view. Seven radiation patches (302) are respectively laid at the centers of the six regular hexagon microstrip coils (102) on the third base layer (301) and the center of the closed array. Two feeding holes (303) are provided on each of the radiation patches (302). The lower surface of the third base layer (301) is copper-plated as the metal ground.

[0006] Further, the thickness of the middle layer structure (20) is adjustable.

[0007] Further, the circular antenna array is provided with a plurality of metallized vias. The metallized vias are arranged on the edges of each regular hexagon microstrip coil (102) on the upper surface of the first base layer (101) of the top layer structure (10), penetrate through the entire antenna array, and extend to the metal ground on the lower surface of the third base layer (301) of the bottom layer structure (30).

[0008] Further, the distance between the centers of adjacent regular hexagon microstrip coils (102) is 0.75λ, where λ is the operating wavelength of the highest operating frequency.

[0009] Further, the materials of the top layer structure (10), the middle layer structure (20), and the bottom layer structure (30) are high-frequency base materials with a dielectric constant of 3.5 and prepregs.

[0010] A full array antenna is formed by arranging a plurality of the above circular antenna arrays.

[0011] The advantages of the present utility model are as follows:

[0012] The utility model adopts a dual-patch form of a radiation patch and a parasitic patch, feeds the antenna array through the feeding holes on the third substrate layer, the radiation patch on the third substrate layer generates radiation, and the parasitic patch on the first substrate layer introduces new resonance points, thereby expanding the working bandwidth of the antenna. The impedance matching within the working frequency band of the antenna array is adjusted by adjusting the thickness of the second substrate layer; the feeding holes of the antenna array units are arranged in a triangular grid, and the element spacing design of the antenna can be increased on the premise that grating lobes do not appear at the same scanning angle; the metal wall structure can increase the isolation degree between antenna elements, suppress the propagation of surface waves, suppress high-frequency resonance singularities, improve the mutual coupling strength between elements, and achieve wide-bandwidth and wide-angle scanning in the case of small element spacing, and improve the active standing wave performance of the antenna array scanning. The outer shape of the antenna array unit is designed as a hexagon, which can realize a circular and modularly expandable array layout design. Brief Description of the Drawings

[0013] Figure 1 is a three-dimensional structural schematic diagram of the circular antenna array according to the first embodiment of the utility model;

[0014] Figure 2 is a top view of the top layer structure of the circular antenna array according to the first embodiment of the utility model;

[0015] Figure 3 is a top view of the middle layer structure of the circular antenna array according to the first embodiment of the utility model;

[0016] Figure 4 is a top view of the bottom layer structure of the circular antenna array according to the first embodiment of the utility model;

[0017] Figure 5 is a performance comparison diagram of the circular antenna array with and without a metal wall structure according to the first embodiment of the utility model;

[0018] Figure 6 is a schematic diagram of the full array antenna arraying according to the second embodiment of the utility model;

[0019] Figure 7 is a diagram of the simulation result of the radiation pattern of the full array antenna at the typical frequency point of 14.25 GHz according to the second embodiment of the utility model. Detailed Embodiment

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the utility model clearer, the technical solutions in the embodiments of the utility model will be clearly and completely described below in conjunction with the embodiments of the utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the utility model without creative efforts shall fall within the protection scope of the utility model.

[0021] The technical solution of the present utility model will be further described below in conjunction with the accompanying drawings of the specification and specific embodiments:

[0022] Embodiment 1

[0023] As Figure 1 shown, the circular antenna array of this embodiment has a three-layer structure, namely: a top layer structure (10), an intermediate layer structure (20), and a bottom layer structure (30). The top layer structure (10), the intermediate layer structure (20), and the bottom layer structure (30) are aligned and pressed together in order from top to bottom. The materials of the top layer structure (10), the intermediate layer structure (20), and the bottom layer structure (30) are high-frequency substrates with a dielectric constant of 3.5 and pp prepregs.

[0024] As Figure 2 shown, on the upper surface of the first base layer (101) of the top layer structure (10), 6 regular hexagon microstrip coils (102) are laid. The 6 regular hexagon microstrip coils (102) are rotationally connected at 360° with the center of the first base layer (101) as the center to form a closed array with 7 regular hexagon antenna array units. The 6 regular hexagon microstrip coils (102) share one side between each other; 7 parasitic patches (103) are respectively laid at the centers of the 6 regular hexagon microstrip coils (102) and the center of the closed array; a plurality of metallized vias are opened on the sides of each regular hexagon microstrip coil (102).

[0025] As Figure 3 shown, on the second base layer (201) of the intermediate layer structure (20), a plurality of metallized vias corresponding one by one to the metallized vias on the first base layer (101) are opened.

[0026] As Figure 4 shown, on the upper surface of the third base layer (301) of the bottom layer structure (30), a closed array composed of 6 regular hexagon microstrip coils (102) same as that on the upper surface of the first base layer (101) is laid. The projection of the closed array on the upper surface of the third base layer (301) coincides with the projection of the closed array on the upper surface of the first base layer (101) in the top view. 7 radiation patches (302) are respectively laid at the centers of the 6 regular hexagon microstrip coils (102) on the third base layer (301) and the center of the closed array. Two feed holes (303) are provided on each of the radiation patches (302). The lower surface of the third base layer (301) is copper-plated as the metal ground.

[0027] As Figures 1 to 4As shown in the figure, a plurality of metallized vias are formed in the antenna array. The metallized vias are arranged on the edges of each regular hexagonal microstrip coil (102) on the upper surface of the first base layer (101) of the top layer structure (10), penetrate through the entire antenna array, and extend to the metal ground on the lower surface of the third base layer (301) of the bottom layer structure (30), thereby forming a metal wall structure. As Figure 5 shown, the metal wall structure can increase the isolation between antenna elements, suppress the propagation of surface waves, suppress the resonant singularities at high frequencies, improve the mutual coupling strength between elements, achieve wideband wide-angle scanning in the case of small spacing, and improve the active standing wave performance of the antenna array scanning.

[0028] The working principle of the circular antenna array in this embodiment is as follows:

[0029] Adopt the double patch form of the radiation patch (302) and the parasitic patch (103) to improve the bandwidth. Feed the antenna array through the feed hole (303) of the third base layer (301). The radiation patch (302) on the third base layer (301) generates radiation and emits radio frequency signals externally. The parasitic patch (103) on the first base layer (101) introduces new resonant points, thereby expanding the working bandwidth of the antenna. Impedance matching within the working frequency band of the antenna array is achieved by adjusting the thickness of the second base layer (201); the feed holes (303) of the antenna array units are arranged in a triangular grid, and the element spacing of the antenna can be increased on the premise that there are no grating lobes at the same scanning angle; the outer shape of the antenna array unit is designed as a hexagon, which can realize the circular and modular expandable array design; according to the access standard of the satellite terminal pattern, there should be no grating lobes in the ±35° scanning range of the antenna array. Through the calculation of the condition that there are no grating lobes in the antenna array scanning, the spacing of the antenna array units is 0.75λ, where λ is the working wavelength of the highest operating frequency.

[0030] Embodiment 2

[0031] As Figure 6 shown, a full array antenna is formed by arranging 7 circular antenna arrays in Embodiment 1 in an array. As Figure 7 shown, the figure shows the pattern simulation results of the full array antenna at the typical frequency point of 14.25 GHz. It can be seen from the figure that the full array antenna can achieve a beam scanning ability of 35° without grating lobes.

[0032] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A circular antenna array, characterized in that: include: A top layer structure (10), an intermediate layer structure (20), and a bottom layer structure (30), wherein the top layer structure (10), the intermediate layer structure (20), and the bottom layer structure (30) are aligned and pressed together in order from top to bottom; six regular hexagonal microstrip coils (102) are laid on the upper surface of the first base layer (101) of the top layer structure (10); the six regular hexagonal microstrip coils (102) are connected by rotating 360 degrees with the center of the first base layer (101) as the center to form a closed array with seven regular hexagonal antenna array units; the six regular hexagonal microstrip coils (102) share one side; seven parasitic patches (103) are laid on the six regular hexagonal microstrip coils (102) respectively. ) and the center of the closed array; the upper surface of the third base layer (301) of the bottom structure (30) is provided with a closed array consisting of six regular hexagonal microstrip coils (102) which is the same as the upper surface of the first base layer (101); the closed array on the upper surface of the third base layer (301) overlaps with the closed array on the upper surface of the first base layer (101) in the top view; seven radiation patches (302) are respectively provided at the center of the six regular hexagonal microstrip coils (102) and the center of the closed array on the third base layer (301); each of the radiation patches (302) is provided with two feeding holes (303); and the lower surface of the third base layer (301) is copper-clad as a metal ground.

2. The circular antenna array according to claim 1, characterized in that: The thickness of the intermediate layer structure (20) is adjustable.

3. The circular antenna array according to claim 1, characterized in that: The circular antenna array is provided with a plurality of metallized vias, and the metallized vias are arranged on the sides of each regular hexagonal microstrip coil (102) on the upper surface of the first base layer (101) of the top structure (10), penetrate the entire antenna array, and extend to the metal ground on the lower surface of the third base layer (301) of the bottom structure (30).

4. The circular antenna array according to claim 1, characterized in that: The spacing between the centers of adjacent regular hexagonal microstrip coils (102) is 0.75λ, where λ is the working wavelength of the highest working frequency.

5. The circular antenna array according to claim 1, characterized in that: The materials of the top layer structure (10), the middle layer structure (20) and the bottom layer structure (30) are a high-frequency substrate with a dielectric constant of 3.5 and a prepreg.

6. A full array antenna, characterized in that: A plurality of circular antenna arrays as claimed in any one of claims 1 to 5 are used to form an array.

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