Square antenna array and full-array antenna thereof

Abstract

The utility model relates to a square 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 wide-angle scanning array antenna units. Impedance matching in an antenna array working frequency band is carried out by adjusting the thickness of the second base layer, the isolation degree between array units is improved by introducing the periodic reflection surface patch, the active standing wave performance during array large-angle scanning is improved, the antenna units are arranged in a rectangular grid mode, and the antenna array has a wide application range. And no grating lobe appears during beam scanning at + / -45 degrees.

Description

Technical Field

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

[0002] Common ground terminal antennas for satellite communication include parabolic antennas, array antennas, and phased array antennas. Traditional parabolic antennas and array antennas use mechanical servo systems to track satellites, with large inertia, slow speed, and high profile. The terminal antenna in phased array form is an antenna that changes the pattern pointing by controlling the feeding phase of the radiation units in the antenna, with fast response and low profile. The phased array antenna is the development trend of the terminal 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 the terminal antenna, 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 is enhanced, 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 wide-angle scanning array antenna elements.

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

[0005] A square antenna array includes: 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 the order from top to bottom. On the upper surface of the first base layer (101) of the top layer structure (10), 16 parasitic patches (102) are laid. The 16 parasitic patches (102) are evenly arranged in a 4×4 array on the upper surface of the first base layer (101). On the upper surface of the third base layer (301) of the bottom layer structure (30), 16 radiation patches (302) corresponding to the 16 parasitic patches (102) on the upper surface of the first base layer (101) are laid. The 16 radiation patches (302) are evenly arranged in a 4×4 array on the upper surface of the third base layer (301) to form 16 antenna elements. The central points of the 16 parasitic patches (102) on the upper surface of the first base layer (101) coincide with the projections of the central points of the 16 radiation patches (302) on the upper surface of the third base layer (301) in the top view. Two feeding holes (303) are provided on each of the radiation patches (302), and the lower surface of the third base layer (301) is copper-plated as the metal ground.

[0006] Further, a plurality of periodic reflection surface patches (304) are evenly laid on the upper surface of the third base layer (301). The periodic reflection surface patches (304) are copper sheets in any polygon shape, and their sizes are less than or equal to one-quarter of the working wavelength of the highest operating frequency.

[0007] Further, the thickness of the intermediate layer structure (20) is adjustable.

[0008] Further, the distance between the centers of adjacent antenna elements is 0.58λ, where λ is the working wavelength of the highest operating frequency.

[0009] Further, the materials of the top layer structure (10), the intermediate 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 arraying a plurality of the above-mentioned square antenna arrays.

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

[0012] The present invention adopts a double-patch form of radiation patches and parasitic patches to improve the bandwidth. The parasitic patches introduce 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 base layer. The isolation degree between array elements is improved by introducing periodic reflection surface patches, and the active standing wave performance during large-angle scanning of the array is improved. The arrangement of the antenna elements is in a rectangular grid arrangement, and no grating lobes appear during beam scanning of ±45°. Description of the Drawings

[0013] Figure 1 is a three-dimensional structural schematic diagram of the square antenna array according to the first embodiment of the present invention;

[0014] Figure 2 is a top view of the top layer structure of the square antenna array according to the first embodiment of the present invention;

[0015] Figure 3 is a top view of the middle layer structure of the square antenna array according to the first embodiment of the present invention;

[0016] Figure 4 is a top view of the bottom layer structure of the square antenna array according to the first embodiment of the present invention;

[0017] Figure 5 is a comparison diagram of simulation results of adding parasitic patches and not adding parasitic patches of the square antenna array according to the first embodiment of the present invention;

[0018] Figure 6 is a comparison diagram of simulation results of adding periodic reflection surface patches and not adding periodic reflection surface patches of the square antenna array according to the first embodiment of the present invention;

[0019] Figure 7 is a schematic diagram of the full array antenna arraying according to the second embodiment of the present invention;

[0020] Figure 8 is a pattern simulation result diagram of the full array antenna at the typical frequency point of 14.25 GHz according to the second embodiment of the present invention. Detailed Embodiment

[0021] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] The technical solutions of the present invention will be further described below in conjunction with the drawings of the specification and specific embodiments:

[0023] Embodiment 1

[0024] As Figure 1As shown in the figure, the circular antenna array of this embodiment has a three-layer structure, namely: 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. The materials of the top layer structure (10), the middle layer structure (20), and the bottom layer structure (30) are high-frequency substrates with a dielectric constant of 3.5 and prepregs.

[0025] As Figure 2 shown in the figure, on the upper surface of the first base layer (101) of the top layer structure (10), 16 parasitic patches (102) are laid. The 16 parasitic patches (102) are evenly arranged in a 4×4 array on the upper surface of the first base layer (101) to form 16 antenna elements.

[0026] As Figure 3 shown in the figure, the thickness of the second base layer (201) of the middle layer structure (20) is adjustable, and impedance matching within the working frequency band of the antenna array is achieved by adjusting the thickness of the second base layer (201).

[0027] As Figure 4 shown in the figure, on the upper surface of the third base layer (301) of the bottom layer structure (30), 16 radiation patches (302) corresponding to the 16 parasitic patches (102) on the upper surface of the first base layer (101) are laid. The 16 radiation patches (302) are evenly arranged in a 4×4 array on the upper surface of the third base layer (301). The center points of the 16 parasitic patches (102) on the upper surface of the first base layer (101) coincide with the projections of the center points of the 16 radiation patches (302) on the upper surface of the third base layer (301) in the top view; two feeding holes (303) are provided on each of the radiation patches (302), and the lower surface of the third base layer (301) is copper-plated as the metal ground. A plurality of periodic reflection surface patches (304) are also evenly laid on the upper surface of the third base layer (301). The periodic reflection surface patches (304) can be copper sheets of any polygon, and their sizes are less than or equal to one-quarter of the working wavelength of the highest operating frequency.

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

[0029] Adopt a dual-patch form of a radiating patch (302) and a parasitic patch (102) to improve the bandwidth. Feed the antenna array through the feeding hole (303) of the third substrate layer (301). The radiating patch (302) on the third substrate layer (301) generates radiation and externally emits radio frequency signals. The parasitic patch (102) on the first substrate layer (101) introduces new resonance points, thereby expanding the operating bandwidth of the antenna. Impedance matching within the operating frequency band of the antenna array is achieved by adjusting the thickness of the second substrate layer (201). The isolation between array elements is improved by introducing a periodic reflective surface patch, and the active standing wave performance during large-angle scanning of the array is improved. The arrangement of the antenna elements is in a rectangular grid arrangement. To meet the network access standard of the satellite terminal, the scanning range is ±45°; when the beam scans ±45°, no grating lobes appear, and the element spacing needs to satisfy ≤λ / (1 + sin(45deg)), that is, the element spacing needs to satisfy not exceeding 0.58λ. Therefore, the element spacing of the antenna elements is determined to be 0.58λ, where λ is the operating wavelength of the highest operating frequency.

[0030] As Figure 5 shown, it is a comparison of the simulation results with and without the parasitic patch. It can be seen that the parasitic patch introduces new resonance points, thereby expanding the operating bandwidth of the antenna. As Figure 6 shown, it is a comparison of the simulation results with and without the periodic reflective surface patch. It can be seen that the electric field phase coupled by the periodic reflective surface patch (304) is the same as the electric field phase received by the antenna itself from the transmitting antenna, and the electromagnetic waves are in-phase superposition, which can effectively improve the isolation between antenna elements and suppress the propagation of surface waves in the medium, thereby improving the active standing wave performance of the antenna during large-angle scanning.

[0031] Embodiment 2

[0032] As Figure 7 shown, it is a full-array antenna of a 4×4 array composed of 16 square antenna arrays in Embodiment 1. As Figure 8 shown, it is the simulation result of the radiation pattern of this full-array antenna at the typical frequency point of 14.25 GHz. It can be seen from the figure that this full-array antenna can achieve a beam scanning ability of 45° without grating lobes.

[0033] 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 on 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 square 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 a top-to-bottom order; 16 parasitic patches (102) are laid on the upper surface of a first base layer (101) of the top layer structure (10); the 16 parasitic patches (102) are evenly arranged on the upper surface of the first base layer (101) in a 4×4 array to form 16 antenna units; 16 parasitic patches (102) are laid on the upper surface of a third base layer (301) of the bottom layer structure (30) The radiating patches (302) corresponding to the 16 parasitic patches (102) on the upper surface of the first layer (101) are evenly arranged on the upper surface of the third base layer (301) in a 4×4 array, and the center points of the 16 parasitic patches (102) on the upper surface of the first base layer (101) and the projections of the center points of the 16 radiating patches (302) on the upper surface of the third base layer (301) on the top view coincide with each other; each of the radiating 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 square antenna array according to claim 1, characterized in that: A plurality of periodic reflection surface patches (304) are evenly laid on the upper surface of the third base layer (301), wherein the periodic reflection surface patches (304) are copper sheets of arbitrary polygonal shapes, and the size of the copper sheets is less than or equal to one quarter of the working wavelength of the highest working frequency.

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

4. The square antenna array according to claim 1, characterized in that: The spacing between the centers of adjacent antenna units is 0.58λ, where λ is the working wavelength of the highest working frequency.

5. The square 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 square antenna arrays as described in any one of claims 1 to 5 are used to form an array.

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