High-density dual-polarization edge-fire antenna unit based on glass substrate and liquid crystal material

Abstract

The invention discloses a broadband dual-polarization edge-fire antenna unit based on a glass substrate and a liquid crystal material, which comprises a plurality of layers of dielectric substrates, and is characterized in that the lower surface of a first dielectric substrate is provided with a metal floor and four feed ports; a first glass layer is arranged between the first dielectric substrate and the second dielectric substrate; a second glass layer is arranged between the second dielectric substrate and the third dielectric substrate; holes are punched along the two diagonal lines of the first dielectric substrate, and solid third metal columns penetrate through the holes; through holes are punched along the peripheries and centers of the first dielectric substrate, the first glass layer and the second dielectric substrate, a plurality of first metal columns are uniformly distributed in the through holes at the peripheries, and four second metal columns are uniformly distributed in the through hole at the center as feed probes; and the four feed ports are communicated with the radiation patch on the lower surface of the second glass layer through the four second metal columns. According to the invention, the radiation gain and bandwidth of the antenna are effectively improved.

Description

Technical Field

[0001] The invention belongs to the technical field of liquid crystal devices, and in particular relates to a high-density dual-polarization side-firing antenna unit based on a glass substrate and liquid crystal materials. Background Art

[0002] The maximum radiation direction of the broadside antenna is perpendicular to the antenna array surface, which is easy to integrate and very suitable for mobile terminal communications. Broadside antenna units generally include patch antennas, dielectric resonant antennas, slot antennas, and so on. Patch antennas, as a more common broadside antenna, are now widely used in terminal devices. However, in the prior art, most of the research on dual-polarized broadside antennas is based on low frequencies, and is generally single-polarized in high frequency bands. At the same time, the structure of the antenna is mainly based on conventional dielectric substrates, with high production costs and lack of configurability. After the array is formed, the function is often single, and it is difficult to achieve ideal results.

[0003] Liquid crystal materials have attracted the attention of researchers for many years due to their sensitivity to electromagnetic fields and low loss. Liquid crystal has strong electrical tunability, and its characteristics can be controlled by surface anchoring, external electric field or magnetic field. Under different voltages, liquid crystal exhibits different dielectric constants. Compared with traditional dielectric substrates, glass-encapsulated liquid crystal materials as dielectric substrates have low cost and configurable characteristics. In recent years, due to the improvement of lithography and liquid crystal packaging technology, glass substrate antennas have become one of the cutting-edge research directions. Conventional liquid crystal antennas can only transmit electromagnetic energy through coupling due to the limitations of the properties of the glass plate itself, but this solution will bring about greater energy loss. With the introduction of the latest processing technology TGV, it has been proven to be a feasible solution to complete metallized vias on the glass substrate that encapsulates liquid crystals, which undoubtedly provides new ideas for the design of liquid crystal antennas. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material, which realizes the dual-polarization design of the side-firing antenna, so that the antenna has the characteristics of low loss and high gain while having a wider working bandwidth.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material comprises a plurality of dielectric substrates, which are a first dielectric substrate, a second dielectric substrate, and a third dielectric substrate stacked in sequence from bottom to top; wherein:

[0007] A metal floor and a feeding port are arranged on the lower surface of the first dielectric substrate, and the feeding port includes four;

[0008] A first glass layer is provided between the first dielectric substrate and the second dielectric substrate;

[0009] A second glass layer is provided between the second dielectric substrate and the third dielectric substrate;

[0010] Drill holes along two diagonal lines of the first dielectric substrate, and insert solid third metal pillars through each hole;

[0011] Drilling holes around the first dielectric substrate, the first glass layer, and the second dielectric substrate and in the center, evenly distributing a plurality of first metal pillars in the holes around the periphery, and evenly distributing four second metal pillars as feeding probes in the via hole in the center;

[0012] The upper surface and the lower surface of the second glass layer are respectively provided with radiation patches, and the four second metal pillars connect the four feeding ports with the radiation patches on the lower surface of the second glass layer.

[0013] Furthermore, the second dielectric substrate is a liquid crystal material.

[0014] Furthermore, there are a plurality of third metal pillars, which are evenly distributed along the holes on two diagonal lines of the first dielectric substrate.

[0015] Furthermore, the four feeding ports have the same structure, wherein the first port and the third port are evenly distributed on the longitudinal symmetry axis of the first dielectric substrate, and the second port and the fourth port are evenly distributed on the transverse symmetry axis of the first dielectric substrate.

[0016] Furthermore, the distances between the four feeding ports and the intersection of the horizontal and vertical symmetry axes of the first dielectric substrate are equal.

[0017] Furthermore, the first port and the third port are excited in the horizontal polarization state, and the phase difference is 180°; the second port and the fourth port are excited in the vertical polarization state, and the phase difference is 180°.

[0018] Furthermore, when a plurality of the side-firing antenna units form an antenna array, adjacent side-firing antenna units share the plurality of first metal pillars.

[0019] Furthermore, the upper surface of the first dielectric substrate also includes a metal gap.

[0020] Furthermore, the metal gap is in the shape of a flower, and its four protruding petals coincide with the four feeding ports.

[0021] Furthermore, the radius of the feeding port is greater than the radius of the petals.

[0022] The beneficial effects of the present invention are:

[0023] The invention provides a high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material, which improves polarization isolation by adopting a differential feeding form and realizes symmetry of the antenna unit radiation pattern; a single unit has four ports, a first port and a third port are excited in a horizontal polarization state with a phase difference of 180°, and a second port and a fourth port are excited in a vertical polarization state with a phase difference of 180°, thereby realizing co-aperture dual polarization of the antenna unit; a cavity-type dielectric plate improves the bandwidth of the entire unit by an intermediate metal gap, and at the same time, by dividing an entire cavity into four triangular cavities, the isolation between different ports can be significantly improved; a double-layer radiation patch form is adopted to expand the bandwidth, and at this time, the metal gap and the double-layer radiation patch form a Yagi-like structure, which provides different resonance points and also improves the antenna radiation gain; the unit beam width can be changed by adjusting the height of the surrounding metal walls, and the antenna gain can also be improved by adjusting the beam width; the unit beam width can be changed by adjusting the height of the surrounding second metallized holes to improve the antenna gain. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of the three-dimensional structure of the side-firing antenna unit in an embodiment of the present invention;

[0025] Figure 2 is a front view schematic diagram of a broadside antenna unit in an embodiment of the present invention;

[0026] Figure 3 Schematic diagram of a top view of a broadside antenna unit in an embodiment of the present invention;

[0027] Figure 4 is a schematic top view of a broadside antenna array according to an embodiment of the present invention;

[0028] Figure 5 Schematic diagram of return loss of vertical polarization under different liquid crystal dielectrics of a side-firing antenna unit in an embodiment of the present invention;

[0029] Figure 6 Schematic diagram of insertion loss of vertical polarization of a side-firing antenna unit under different liquid crystal dielectrics in an embodiment of the present invention;

[0030] Figure 7 Schematic diagram of the gain of the side-firing antenna unit under vertical polarization under different liquid crystal dielectrics in an embodiment of the present invention.

[0031] Reference numerals:

[0032] 1. First dielectric substrate, 2. First glass layer, 3. Second dielectric substrate, 4. Second glass layer, 5. Third dielectric substrate, 6. Via hole, 7. Third metal column, 8. Feed port, 9. Radiation patch, 10. Metal gap, 6-1. First metal column, 6-2. Second metal column, 8-1. First port, 8-2. Second port, 8-3. Third port, 8-4. Fourth port. DETAILED DESCRIPTION

[0033] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0034] like Figure 1-Figure 3 As shown, the present invention proposes a high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material, comprising:

[0035] Multilayer dielectric substrates are made using multilayer printed circuit board technology, such as Figure 2 As shown, the multi-layer dielectric substrates are: a first dielectric substrate 1, a second dielectric substrate 3, and a third dielectric substrate 5; wherein:

[0036] The first dielectric substrate 1 is rectangular, and a metal layer is provided on its lower surface as a large floor and a feeding port 8 is provided. The feeding port 8 includes four identical ports, namely a first port 8-1, a second port 8-2, a third port 8-3, and a fourth port 8-4. The first port 8-1 and the third port 8-3 are evenly distributed on the longitudinal symmetry axis of the first dielectric substrate 1, and the second port 8-2 and the fourth port 8-4 are evenly distributed on the transverse symmetry axis of the first dielectric substrate 1. The distances from the four ports to the intersection of the transverse and longitudinal symmetry axes are equal.

[0037] The center of the upper layer of the first dielectric substrate 1 is a metal gap 10, and the metal gap 10 may be in the shape of a flower, and its four protruding petals coincide with the four feeding ports, and the radius of the feeding port is greater than the radius of the petals; Figure 3 As shown, one implementation method is given, the metal gap 10 is four small circles with a radius r evenly hollowed out on a large circle with a radius R, R>r, and the radius of the feeding port is also greater than r.

[0038] The second dielectric substrate 3 is a liquid crystal material;

[0039] Furthermore, a first glass layer 2 is provided between the first dielectric substrate 1 and the second dielectric substrate 3;

[0040] A second glass layer 4 is provided between the second dielectric substrate 3 and the third dielectric substrate 5;

[0041] Holes are punched at equal intervals along the diagonal of the first dielectric substrate 1, and solid third metal pillars 7 are passed through each of the equally spaced holes; in addition, via holes 6 are punched along the first dielectric substrate 1, the first glass layer 2, and the second dielectric substrate 3, and first metal pillars 6-1 and second metal pillars 6-2 are arranged in the via holes 6 according to different functions. Several first metal pillars 6-1 are evenly distributed in the via holes 6 around the antenna unit to improve isolation. The upper and lower surfaces of the second glass layer 4 are provided with radiation patches 9, respectively. Four second metal pillars 6-2 serve as feeding probes, and are used to connect the feeding port 8 and the radiation patch 9 on the lower surface of the second glass layer 4.

[0042] As one of the optional implementation schemes, the material of the multi-layer dielectric substrate is Rogers 4360, the thickness of each layer of the dielectric substrate is 0.2 mm, and according to the processing technology, the third metal column 7, the first metal column 6-1, and the second metal column 6-2 are selected with a radius of 0.1 mm.

[0043] like Figure 3 As shown, the via 7 for placing the third metal pillar 7 is 2 mm high, and the via 6 is 5 mm high. The third metal pillars 7 are evenly spaced along the diagonal of the first dielectric substrate 1, making the antenna unit structure completely symmetrical and divided into four parts, effectively improving the port isolation.

[0044] like Figure 4 As shown, the first metal column 6-1 can be shared when forming an array with adjacent units to achieve a high-density arrangement. For the third dielectric substrate 5, the evenly arranged vias 6 below it and the upper radiation patch 9 as a whole are equivalent to forming an effective substrate integrated waveguide metal back cavity, which replaces the metal resonant cavity for radiation. The antenna is fed in the form of back feeding. The second metal column 6-2 can be regarded as a feeding probe that passes from the lower surface of the second glass layer 4 to the upper surface of the second dielectric substrate 3. This feeding design can isolate the antenna feeding structure from the outside world and reduce external interference. The radiation patch 9 is located on the upper and lower surfaces of the second glass layer 4, and transmits radiation energy through coupling.

[0045] Reference again Figure 3The broadband co-aperture dual-polarization side-firing antenna unit based on glass substrate and liquid crystal material adopts the form of probe feeding. In order to make the dual-polarization antenna unit directional diagram symmetrical, differential feeding is adopted and the polarization isolation is improved. A single antenna unit includes a feeding port 8. In the horizontal polarization state, the first port 8-1 and the third port 8-3 are excited, and the phase difference is 180°; in the vertical polarization state, the second port 8-2 and the fourth port 8-4 are excited, and the phase difference is 180°, so as to realize the co-aperture dual polarization of the antenna. The multi-layer dielectric substrate constitutes a cavity. The metal gap 10 on the upper surface of the first dielectric substrate 1 is used to improve the bandwidth of the entire unit. At the same time, combined with the third metal column 7, the entire cavity is divided into four completely symmetrical triangular cavities S1, S2, S3, and S4, which can significantly improve the isolation between different ports. At the same time, a double-layer radiation patch is used to expand the bandwidth. At this time, the radiation gap and the double-layer patch form a Yagi-like structure, which provides different resonance points while also improving the antenna radiation gain. Finally, the unit beam width can be changed by adjusting the height of the surrounding vias 6, and the antenna gain can be improved by adjusting the beam width.

[0046] Figure 5 Figure 6 , Figure 7 The overall parameters of the present invention under typical liquid crystal dielectric constants of 2.46 to 3.57 are respectively shown, which are the dual-polarization return loss, insertion loss and gain radiation pattern of the representative device, all of which show that the design effect of the present invention is good. It should be noted that since the antenna unit structure is completely symmetrical, the values ​​of the electromagnetic parameters of the horizontal and vertical polarizations are exactly the same, and only the mathematical coordinates are different. Therefore, the figures in this article only show the data of the vertical polarization.

[0047] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material, characterized in that: It comprises a plurality of dielectric substrates, which are a first dielectric substrate, a second dielectric substrate and a third dielectric substrate stacked in sequence from bottom to top; wherein: A metal floor and a feeding port are arranged on the lower surface of the first dielectric substrate, and the feeding port includes four; A first glass layer is provided between the first dielectric substrate and the second dielectric substrate; A second glass layer is provided between the second dielectric substrate and the third dielectric substrate; Drill holes along two diagonal lines of the first dielectric substrate, and insert solid third metal pillars through each hole; Drilling holes around the first dielectric substrate, the first glass layer, and the second dielectric substrate and in the center, evenly distributing a plurality of first metal pillars in the holes around the periphery, and evenly distributing four second metal pillars as feeding probes in the via hole in the center; The upper surface and the lower surface of the second glass layer are respectively provided with radiation patches, and the four second metal pillars connect the four feeding ports with the radiation patches on the lower surface of the second glass layer.

2. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 1, characterized in that: The second dielectric substrate is made of liquid crystal material.

3. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 1, characterized in that: There are a plurality of third metal pillars, which are evenly distributed along the holes on the two diagonal lines of the first dielectric substrate.

4. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 1, characterized in that: The four feeding ports have the same structure, wherein the first port and the third port are evenly distributed on the longitudinal symmetry axis of the first dielectric substrate, and the second port and the fourth port are evenly distributed on the transverse symmetry axis of the first dielectric substrate.

5. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 4, characterized in that: The four feeding ports are at equal distances from the intersection of the horizontal and vertical symmetry axes of the first dielectric substrate.

6. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 4, characterized in that: In the horizontal polarization state, the first port and the third port are excited, and the phase difference is 180°; in the vertical polarization state, the second port and the fourth port are excited, and the phase difference is 180°.

7. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 1, characterized in that: When a plurality of the side-firing antenna units form an antenna array, adjacent side-firing antenna units share the plurality of first metal pillars.

8. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 1, characterized in that: The upper surface of the first dielectric substrate also includes a metal gap.

9. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 8, characterized in that: The metal gap is in a flower shape, and its four protruding petals coincide with the four feeding ports.

10. The high-density dual-polarization side-firing antenna unit based on a glass substrate and a liquid crystal material according to claim 9, characterized in that: The radius of the feeding port is greater than the radius of the petals.

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