Two-dimensional broadband wide beam coverage phased-array antenna and wide beam generation method thereof

Abstract

The invention discloses a two-dimensional broadband wide beam coverage phased-array antenna and a wide beam generation method thereof, and belongs to the technical field of antennas. The phased-array antenna is composed of a plurality of 2 * 2 antenna modules, the antenna is distributed in an axial symmetry mode, an offset feed mode is adopted, and interconnection with an external T / R assembly through BGA ball mounting is facilitated; meanwhile, through the arc-shaped transition structure and the coupling feed structure of the H-shaped gap, the insertion loss is reduced, the matching is improved, and the bandwidth is improved. And furthermore, based on the structure, an excitation value required by the two-dimensional wide beam is analyzed through an improved comprehensive algorithm, the applicability is high, and the calculation is simple and quick. On the basis, a tile type phased array system is adopted, the amplitude and the phase are easy to regulate and control, and the in-band gain flatness and the beam width can be freely adjusted and reconstructed. Therefore, the antenna has the structural advantages of simple structure, low profile, high integration level and the like, and can realize the performances of wide working band, two-dimensional wide beam coverage and easy beam regulation and control.

Description

Technical Field

[0001] The present invention belongs to the field of antenna technology, and in particular relates to a two-dimensional wide bandwidth beam coverage phased array antenna and a wide beam generation method thereof. Background Art

[0002] In the fields of radar and communication, such as aviation surveillance and naval navigation, broadband communication is required on the one hand, and a wide target detection range is required on the other hand, which puts forward new requirements for wide-bandwidth angular domain beam coverage on the system. Omnidirectional antennas can achieve wide-angular domain beam coverage, but their gain is low, multipath effect is serious, and airspace anti-interference ability is poor; while narrowband narrow beam directional antennas cannot adapt to broadband, large angular domain, and high dynamic target communication. Two-dimensional wide beam can achieve uniform coverage of signals within a two-dimensional rectangular range, reduce multipath effect, and improve the anti-interference ability of signals in space through spatial filtering, thereby improving communication quality, and at the same time improve channel capacity through spatial multiplexing. At present, there are conformal antennas that can achieve high-gain two-dimensional wide beams, but such antennas are bulky and have high requirements for the installation environment; there are also array antennas achieved by shaping, but it is necessary to design a complex feeding network, resulting in narrow bandwidth, and both types of antennas are not conducive to miniaturization and integration.

[0003] Each antenna unit of the phased array is interconnected with the T / R component module. By adjusting the attenuator and phase shifter to change the excitation amplitude and phase of the antenna unit, different beam shapes and directions can be easily and quickly achieved. Compared with the traditional brick-type phased array, the tile-type phased array has the advantages of low profile and easy integration, but it requires the symmetry of the feeding position of the antenna module. Therefore, a simple antenna unit is designed that can be easily interconnected and matched with the tile-type T / R component module. Summary of the invention

[0004] In order to solve the existing technical problems, the present invention provides a two-dimensional wide bandwidth beam coverage phased array antenna and a wide beam generating method thereof.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A two-dimensional wide bandwidth beam coverage phased array antenna, composed of a plurality of antenna modules arranged in a rectangular grid, each antenna module consisting of 2×2 antenna units, and the antenna units are axially symmetrically distributed; each antenna unit comprises a metal shielding hole, a feed probe and a feed shielding hole, and a metal stratum, a first dielectric layer, a feed line layer, a first prepreg layer, a second dielectric layer, a coupling slot layer, a second prepreg layer, a third dielectric layer, a lower patch layer, a third prepreg layer, a fourth dielectric layer, a fourth prepreg layer, a fifth dielectric layer and an upper patch layer that are closely attached from bottom to top;

[0007] Each antenna unit is equally divided into four areas, the feeding probe is located in any one of the areas, a plurality of feeding shielding holes surround the feeding probe, and the feeding probe and the feeding shielding holes penetrate from the metal layer to the first prepreg layer;

[0008] Each antenna unit is surrounded by a plurality of metal shielding holes, and the metal shielding holes penetrate from the metal ground layer to the coupling slot layer;

[0009] The feed line layer includes an arc-shaped microstrip line and a straight microstrip line. The starting point of the arc-shaped microstrip line is connected to the feeding probe, and the end point is located at the center point of the antenna. The straight microstrip line is connected to the end point of the arc-shaped microstrip line.

[0010] Furthermore, the coupling slot layer is a coupling H-shaped slot, and the center of the coupling H-shaped slot coincides with the center of the antenna unit in the vertical direction.

[0011] Furthermore, the phased array antenna is interconnected with external T / R components through BGA ball planting.

[0012] A two-dimensional wide beam forming method based on the above phased array antenna includes the following process:

[0013] Based on the Woodward pattern synthesis method, the expected far-field pattern is sampled at different discrete positions to obtain the amplitude and phase of the electric field radiated by each antenna unit required for the phased array antenna to generate a two-dimensional wide beam, and a correction factor is added. Make corrections, i is the row number of the phased array antenna, and obtain the excitation amplitude value and phase value of each antenna unit;

[0014] By changing the excitation amplitude and phase values ​​of each antenna unit input by the external T / R component, the required beam is generated through the phased array antenna.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] (1) The present invention adopts an offset feeding method of a circular arc microstrip line coupled with an H-shaped slot, which realizes the axisymmetric structure of the antenna module in terms of structure, which is conducive to interconnection with the T / R component; in terms of performance, it reduces the loss caused by transition and switching, improves the matching of the phased array antenna, and increases the bandwidth of the antenna.

[0017] (2) The present invention can quickly obtain the excitation amplitude and phase distribution required for a two-dimensional wide beam through an improved synthesis algorithm, and is suitable for the synthesis of far-field radiation patterns of any unit form and any scale. The calculation method is simple and the calculation result is unique.

[0018] (3) The present invention adopts a tiled phased array system to achieve two-dimensional wide beam coverage, and achieves miniaturization, low profile, and high integration in structure; in terms of function, the amplitude and phase are easy to control, and the in-band gain flatness and beam width can be freely adjusted and reconstructed, and even beam scanning can be performed within the angle range allowed by the design. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the three-dimensional structure of a two-dimensional wide bandwidth beam coverage phased array antenna in an embodiment of the present invention.

[0020] Figure 2 It is a schematic diagram of the topological structure of the two-dimensional wide bandwidth beam coverage phased array antenna in the present invention.

[0021] Figure 3 It is a top view of an antenna module of a two-dimensional wide bandwidth beam coverage phased array antenna in an embodiment of the present invention.

[0022] Figure 4 It is a schematic diagram of the three-dimensional structure of the interconnection between the antenna module of the two-dimensional wide bandwidth beam coverage phased array antenna and the external T / R component module in an embodiment of the present invention.

[0023] Figure 5 It is a side view of an antenna unit of a two-dimensional wide bandwidth beam coverage phased array antenna in an embodiment of the present invention.

[0024] Figure 6 It is a top view of the feeding structure of the two-dimensional wide bandwidth beam coverage phased array antenna in an embodiment of the present invention.

[0025] Figure 7 4 is a standing wave ratio curve diagram of the antenna module in an embodiment of the present invention.

[0026] Figure 8 It is the 3D radiation pattern of the two-dimensional wide beam at the center frequency of the 8×8 phased array antenna in the embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings. However, the present invention can be implemented in different forms and should not be construed as being limited to the embodiments set forth herein.

[0028] This embodiment provides an 8×8 two-dimensional wide bandwidth beam coverage phased array antenna operating in the Ku band, and its structural schematic diagram is shown in FIG. Figure 1 As shown, the phased array antenna consists of 16 antenna modules, and its topology diagram is shown in Figure 2 As shown; the structural schematic diagram of the antenna module is as shown Figure 3As shown, it includes 2×2 antenna units radiating linear polarized waves, and the antenna units are axially symmetrically distributed along the X-axis and the Y-axis; each antenna module is interconnected with an external T / R component 19 through a BGA ball 18, as shown in FIG. Figure 4 As shown; the antenna unit is as shown Figure 5 As shown, the size is 0.5λ h ×0.5λ h ,λ h It is a high-frequency free-space wavelength, including a metal layer 1, a first dielectric layer 2, a feeding layer 3, a first semi-cured sheet layer 4, a second dielectric layer 5, a coupling gap layer 6, a second semi-cured sheet layer 7, a third dielectric layer 8, a lower patch layer 9, a third semi-cured sheet layer 10, a fourth dielectric layer 11, a fourth semi-cured sheet layer 12, a fifth dielectric layer 13 and an upper patch layer 14, which are tightly fitted from bottom to top, and also include a feeding probe 15, a feeding shielding hole 16 and a metal shielding hole 17.

[0029] The relative dielectric constant of the first dielectric layer 2 is 3.35, and the thickness is 0.2 mm; the relative dielectric constant of the second dielectric layer 5 is 3.35, and the thickness is 0.1 mm; the relative dielectric constants of the third dielectric layer 8, the fourth dielectric layer 11 and the fifth dielectric layer 13 are all 3.35, and the thicknesses are all 0.5 mm.

[0030] The relative dielectric constants of the first to fourth prepreg sheets 4, 7, 10 and 12 are all 3.32, and the thicknesses are all 0.106 mm.

[0031] like Figure 6 As shown, the antenna unit is equally divided into four areas A, B, C, and D along the coordinate axis. The feeding position is located in area A, 0.35 mm from the X-axis of the center point of the antenna, and 1.15 mm from the Y-axis, which is consistent with the output position of the external T / R component 19. The feeding probe 15 sequentially penetrates the metal layer 1 to the first semi-cured sheet layer 4, has a diameter of 0.3 mm, and has pads on the upper and lower surfaces, with a diameter of 0.6 mm. The feeding probe 15 is surrounded by a feeding shielding hole 16, which also penetrates the metal bottom layer 1 to the first semi-cured sheet layer 4, has a diameter of 0.3 mm, and has pads on the upper and lower surfaces, with a diameter of 0.6 mm. The pads on the lower surfaces of the feeding probe 15 and the feeding shielding holes 16 around it are welded to the BGA ball 18.

[0032] The feed layer 3 is located on the upper surface of the first dielectric substrate, and includes an arc-shaped microstrip line and a straight microstrip line. The starting point of the arc-shaped microstrip line is connected to the feed probe 15, and is 0.35 mm from the X axis and 1.15 mm from the Y axis of the center point of the antenna; the end point is located at the center point of the antenna. A straight microstrip line parallel to the X axis is connected to the end point of the arc-shaped microstrip line, and the length of the straight microstrip line is 3.1 mm. The widths of the arc-shaped microstrip line and the straight microstrip line are both 0.2 mm.

[0033] The coupling slot layer 6 is a coupling H-shaped slot, the center of the coupling H-shaped slot coincides with the center of the antenna unit on the Z axis, two long slots are perpendicular to the X axis, the long side length is 2.55 mm, and the short side length is 0.15 mm; one short slot is parallel to the X axis, the long side length is 1.42 mm, and the short side length is 0.13 mm.

[0034] The lower patch layer 9 and the upper patch layer 14 are both square metal patches, and their centers coincide with the center of the antenna unit on a vertical line. The lower patch layer 9 is located on the upper surface of the third dielectric layer 8, and the patch size is 4.1mm×4.1mm. The upper patch layer 14 is located on the upper surface of the fifth dielectric layer 13, and the patch size is 3.92mm×3.92mm.

[0035] The antenna unit is surrounded by a circle of metal shielding holes 17, which sequentially penetrate the metal ground layer 1 to the coupling slot layer 6, and the hole diameter is 0.3 mm.

[0036] The specific process of the two-dimensional wide beam forming method based on the phased array antenna is as follows:

[0037] Through the improved Woodward pattern synthesis method, the expected far-field pattern is sampled at different discrete positions to obtain the amplitude and phase of the electric field radiated by each antenna unit required for the phased array antenna to generate a two-dimensional wide beam, and the correction factor is added. Make corrections, i is the row number of the phased array antenna, and obtain the excitation amplitude value and phase value of each antenna unit;

[0038] The excitation amplitude and phase values ​​input to each antenna element by the external T / R component 19 are changed to generate the required wide beam.

[0039] The antenna module standing wave ratio of this embodiment is simulated and tested, and the results are as follows: Figure 7 As shown, the relative impedance bandwidth of a standing wave ratio of 1.5 is 27.6%.

[0040] like Figure 8 The figure shows the 3D radiation pattern of the 8×8 two-dimensional wide bandwidth beam coverage phased array antenna in this embodiment. The antenna gain is as high as 8.4dBi, and the beam flatness within the two-dimensional 60° range is 1.25dB.

[0041] The above results show that the phased array antenna in the present invention can achieve wide beam coverage of more than 60° in both elevation and azimuth planes within a wider operating frequency band.

[0042] Many specific details are described in the above description to facilitate a full understanding of the present invention. However, the above description is only a preferred embodiment of the present invention. The present invention can be implemented in many other ways different from those described herein, so the present invention is not limited to the specific implementation disclosed above. At the same time, any person familiar with the art can make many possible changes and modifications to the technical solution of the present invention using the methods and technical contents disclosed above without departing from the scope of the technical solution of the present invention, or modify it into an equivalent embodiment of equivalent changes. Any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the scope of protection of the technical solution of the present invention.

Claims

1. A two-dimensional wide bandwidth beam coverage phased array antenna, characterized in that: It is composed of a plurality of antenna modules arranged in a rectangular grid, each antenna module is composed of 2×2 antenna units, and the antenna units are axially symmetrically distributed; each antenna unit includes a metal shielding hole, a feed probe and a feed shielding hole, and a metal layer, a first dielectric layer, a feed line layer, a first prepreg layer, a second dielectric layer, a coupling gap layer, a second prepreg layer, a third dielectric layer, a lower patch layer, a third prepreg layer, a fourth dielectric layer, a fourth prepreg layer, a fifth dielectric layer and an upper patch layer that are closely attached from bottom to top; Each antenna unit is equally divided into four areas, the feeding probe is located in any one of the areas, a plurality of feeding shielding holes surround the feeding probe, and the feeding probe and the feeding shielding holes penetrate from the metal layer to the first prepreg layer; Each antenna unit is surrounded by a plurality of metal shielding holes, and the metal shielding holes penetrate from the metal ground layer to the coupling slot layer; The feed line layer includes an arc-shaped microstrip line and a straight microstrip line. The starting point of the arc-shaped microstrip line is connected to the feeding probe, and the end point is located at the center point of the antenna. The straight microstrip line is connected to the end point of the arc-shaped microstrip line.

2. The two-dimensional wide bandwidth beam coverage phased array antenna according to claim 1, characterized in that: The coupling slot layer is a coupling H-shaped slot, and the center of the coupling H-shaped slot coincides with the center of the antenna unit in the vertical direction.

3. The two-dimensional wide bandwidth beam coverage phased array antenna according to claim 1, characterized in that: The phased array antenna and external T / R components are interconnected through BGA balls.

4. A two-dimensional wide beam forming method based on the phased array antenna according to any one of claims 1 to 3, characterized in that: The process includes: Based on the Woodward pattern synthesis method, the expected far-field pattern is sampled at different discrete positions to obtain the amplitude and phase of the electric field radiated by each antenna unit required for the phased array antenna to generate a two-dimensional wide beam, and a correction factor is added. Make corrections, i is the row number of the phased array antenna, and obtain the excitation amplitude value and phase value of each antenna unit; By changing the excitation amplitude and phase values ​​of each antenna unit input by the external T / R component, the required beam is generated through the phased array antenna.

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