Beidou anti-interference antenna array

Abstract

The invention discloses a Beidou anti-interference antenna array which comprises an antenna array, a decoupling metasurface and an antenna cover. The decoupling metasurface is located between the antenna array and the antenna housing, the antenna array comprises a plurality of antenna array elements, and the plurality of antenna array elements are arranged and printed on a whole PCB to form the antenna array; the decoupling metasurface comprises a plurality of basic structure units which are periodically arranged, each basic structure unit is a bent line annular printed circuit, a basic structure unit equivalent inductor L and a gap equivalent capacitor C between the two basic structure units, and LC resonance can be achieved to block propagation of electromagnetic waves in the plane direction, namely a mutual coupling transmission path is blocked. According to the invention, through the design of the decoupling metasurface, the mutual coupling of the miniaturized Beidou anti-interference antenna array is reduced, and the improvement of the isolation between Beidou anti-interference antenna array elements is realized.

Description

Technical Field

[0001] This invention relates to the field of satellite navigation system technology, and specifically to a BeiDou anti-jamming antenna array. Background Technology

[0002] The BeiDou Navigation Satellite System, independently developed by my country, has wide applications in surveying, mapping, water conservancy, fisheries, transportation, and military fields. However, due to the great distance between navigation satellites and Earth, satellite signals are extremely weak, making them highly susceptible to interference from complex environments or human factors. This interference can lead to navigation signal distortion, decreased accuracy, or even complete loss, severely impacting applications relying on BeiDou navigation. To combat interference, anti-jamming antenna arrays are widely used in BeiDou anti-jamming systems. However, with the miniaturization and densification of antenna arrays, the mutual coupling problem between antenna elements has become increasingly prominent. Mutual coupling not only reduces antenna performance but also affects the system's signal-to-noise ratio, thus impacting the overall system performance. Summary of the Invention

[0003] The purpose of this invention is to provide a BeiDou anti-interference antenna array that improves system performance, enhances anti-interference capability, and promotes antenna array miniaturization through a decoupled metasurface composite integration design, thereby expanding application scenarios.

[0004] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows:

[0005] A BeiDou anti-jamming antenna array includes an antenna array, a decoupling metasurface, and an antenna radome;

[0006] The decoupling metasurface is located between the antenna array and the radome. The antenna array includes multiple antenna elements, which are arranged and printed on a single PCB board to form the antenna array. The decoupling metasurface includes multiple periodically arranged basic structural units. Each basic structural unit is a zigzag ring printed circuit. The equivalent inductance L of the basic structural unit and the equivalent capacitance C of the gap between two basic structural units can achieve LC resonance to block the propagation of electromagnetic waves in the XY plane, that is, to block the mutual coupling transmission path.

[0007] Furthermore, the decoupling metasurface is fabricated using a single-sided PCB.

[0008] Furthermore, the radome is composite-integrated with the decoupling metasurface, and the printed circuit of the decoupling metasurface is encapsulated within a dielectric.

[0009] Furthermore, each side of the zigzag ring-shaped printed circuit is one-quarter of the dielectric wavelength.

[0010] Furthermore, the antenna array element includes a dielectric substrate, a radiating patch, and a coaxial feed probe. The bottom layer of the dielectric substrate is printed copper foil, and the top layer of the dielectric substrate is a radiating patch. The antenna array element receives right-hand circularly polarized waves through the coaxial feed probe and converts free-space waves into guided waves.

[0011] Furthermore, the antenna array element adopts a chamfered single-feed microstrip antenna design, and the right-hand circular polarization characteristic of the array element is achieved through chamfered perturbation.

[0012] Furthermore, the number of antenna array elements is four, and the four antenna array elements are rotated and printed on a single PCB board.

[0013] Compared with the prior art, the technical effects achieved by the present invention are as follows:

[0014] By using a decoupled metasurface composite integration design, the performance of the BeiDou anti-interference antenna array system is improved, its anti-interference capability is enhanced, and the miniaturization of the antenna array is promoted, thereby expanding the application scenarios of the BeiDou anti-interference antenna array.

[0015] 1. This invention reduces the mutual coupling of miniaturized BeiDou anti-interference antenna arrays by designing a decoupled metasurface, thereby improving the isolation between elements of the BeiDou anti-interference antenna array.

[0016] 2. The decoupling metasurface adopts a zigzag-line-like annular periodic structure design, which further reduces the size of the periodic structure through the zigzag design.

[0017] 3. Significantly improves the anti-interference performance of BeiDou anti-interference antenna arrays within the same antenna array size.

[0018] 4. The antenna elements adopt a single-feed perturbation feeding method to achieve right-hand circular polarization, and the antenna array adopts a rotating array arrangement. Attached Figure Description

[0019] Appendix Figure 1 This is a schematic diagram of the three-dimensional structure of the BeiDou anti-interference antenna array;

[0020] Appendix Figure 2 This is a side view of the BeiDou anti-jamming antenna array;

[0021] Appendix Figure 3 This is an exploded view of the BeiDou anti-jamming antenna array.

[0022] Appendix Figure 4 Schematic diagram of decoupled metasurface;

[0023] Appendix Figure 5 A schematic diagram of the basic structural unit of the decoupled metasurface;

[0024] Appendix Figure 6 This is a schematic diagram of a four-element antenna array;

[0025] Appendix Figure 7 This is the main view of the antenna array elements;

[0026] Appendix Figure 8 This is a side view of an antenna array element;

[0027] Appendix Figure 9 A typical isolation variation diagram before and after adding the decoupling metasurface;

[0028] Appendix Figure 10 Comparison of unit radiation patterns before and after adding the decoupled metasurface;

[0029] Appendix Figure 11 Comparison of anti-interference null traps for antenna arrays at typical azimuth 0° and elevation 10° before and after adding a decoupling metasurface. Detailed Implementation

[0030] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0031] like Figure 1-5 As shown, a BeiDou anti-interference antenna array includes an antenna array, a decoupling metasurface, and an antenna radome.

[0032] The decoupling metasurface is located between the antenna array and the radome. The antenna array includes four antenna elements, which are rotated and printed on a single PCB board to form the antenna array (e.g., Figure 6 (as shown); the decoupling metasurface comprises multiple periodically arranged basic structural units (such as...) Figure 5 As shown, each basic structural unit is a zigzag-line ring-shaped printed circuit. The zigzag design transforms straight lines into zigzag lines, reducing the planar size occupied by lines of equal physical length. This facilitates the miniaturization of the antenna array below and further reduces the size of the periodic structure. Each side of the zigzag-line ring-shaped printed circuit is approximately one-quarter of the dielectric wavelength. The equivalent inductance L of the basic structural unit in the XY plane and the equivalent capacitance C of the gap between two basic structural units enable LC resonance to block the propagation of electromagnetic waves in the planar direction, i.e., blocking the mutual coupling transmission path without affecting the normal operation of the antenna. The decoupling metasurface is located above the antenna array and integrated with the radome. The decoupling metasurface uses conventional FR4 material with a dielectric constant of approximately 4.2 as the dielectric substrate and is printed on the upper layer of the dielectric substrate. This reduces the mutual coupling of the miniaturized BeiDou anti-interference antenna array and improves the isolation between the elements of the BeiDou anti-interference antenna array.

[0033] Preferably, the decoupling metasurface is printed on a single-sided PCB.

[0034] Preferably, the radome is composite-integrated with the decoupling metasurface, and the printed circuit of the decoupling metasurface is encapsulated in a dielectric to improve the environmental adaptability (corrosion resistance) of the metasurface. The radome is located on the outermost side of the antenna array, which plays a role in isolating it from the outside world and improving the environmental adaptability of the antenna system. Conventional radome materials (such as fiberglass) are used.

[0035] Preferably, combined with Figure 6-8 The antenna array element includes a dielectric substrate, a radiating patch, and a coaxial feed probe. The bottom layer of the dielectric substrate is a printed copper foil that serves as a ground plane for directional reception, and the top layer of the dielectric substrate is a radiating patch. The antenna array element receives right-hand circularly polarized waves through the coaxial feed probe and converts free-space waves into guided waves.

[0036] Preferably, the antenna elements adopt a conventional chamfered single-feed microstrip antenna design, achieving right-hand circular polarization through chamfer perturbation, and utilize Rogers RO3210 substrate with a relative permittivity of approximately 10.2. The four antenna elements are rotated and printed on a single PCB board. This design is simple in structure, largely unaffected by assembly processes, and offers stable performance and high product consistency. The external power interface for the antenna elements uses a standard 50Ω coaxial cable / connector.

[0037] Figure 9 The typical isolation changes S21, S31, and S41 before and after adding the decoupled metasurface are shown. The left figure shows the metasurface without decoupling, and the right figure shows the metasurface with decoupling.

[0038] Figure 10 The comparison of element radiation patterns before and after adding a decoupling metasurface is shown. The red line represents the element without a decoupling metasurface, and the blue line represents the element with a decoupling metasurface. This improves the element radiation pattern distortion caused by mutual coupling of elements in the miniaturized BeiDou anti-interference antenna array.

[0039] Figure 11 The comparison of anti-interference null traps of antenna arrays at typical azimuth 0° and elevation 10° before and after adding a decoupling metasurface is shown. Red represents the antenna array without a decoupling metasurface, and blue represents the antenna array with a decoupling metasurface. Under the same antenna array size, the anti-interference performance of the BeiDou anti-interference antenna array can be significantly improved.

[0040] Based on the above simulation Figure 9-11 It can be calculated that:

[0041] 1. Taking the center frequency of Beidou B3 as an example, the mutual coupling of units is significantly reduced, and the isolation is improved by more than 10dB.

[0042] 2. Taking the center frequency of Beidou B3 as an example, it significantly improves the element pattern distortion caused by mutual coupling of miniaturized Beidou anti-interference antenna array elements.

[0043] 3. Taking the center frequency of Beidou B3 as an example, under ideal anti-interference amplitude and phase conditions, the zero-dip improvement is more than 4dB after adding a decoupling metasurface.

[0044] 4. Combined with the improved isolation between channels (signal-to-noise ratio enhancement), this decoupled metasurface design will significantly improve the anti-interference performance of the BeiDou anti-interference antenna array.

[0045] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A Beidou anti-interference antenna array, characterized in that: Including antenna arrays, decoupling metasurfaces, and radomes; The decoupling metasurface is located between the antenna array and the antenna cover, the antenna array includes a plurality of antenna elements, and the plurality of antenna elements are arranged and printed on a whole PCB board to form the antenna array; the decoupling metasurface includes a plurality of periodically arranged basic structural units, each basic structural unit is a meander line ring printed circuit, the basic structural unit has an equivalent inductance L, and the gap between two basic structural units has an equivalent capacitance C, which can realize LC resonance to block the propagation of electromagnetic waves in the planar direction, that is, to block the mutual coupling transmission path.

2. The Beidou anti-interference antenna array according to claim 1, characterized in that: The decoupling metasurface is printed on a single-sided PCB.

3. The Beidou anti-interference antenna array according to claim 1, characterized in that: The antenna cover is compositely integrated with the decoupling metasurface, and the printed circuit of the decoupling metasurface is encapsulated in a medium.

4. The Beidou anti-interference antenna array according to claim 1, characterized in that: Each side of the meander line annular printed circuit is a quarter of a dielectric wavelength.

5. The Beidou anti-interference antenna array according to any one of claims 1 to 4, characterized in that: The antenna array element comprises a dielectric substrate, a radiation patch, and a coaxial feeding probe. The bottom layer of the dielectric substrate is a printed copper sheet, and the upper layer of the dielectric substrate is a radiation patch. The antenna array element receives right-hand circularly polarized waves through the coaxial feeding probe to convert free space waves into guided waves.

6. The Beidou anti-interference antenna array according to claim 5, characterized in that: The antenna array element adopts a cut-angle single-fed microstrip antenna design, and realizes the right-hand circular polarization characteristic of the array element through cut-angle perturbation.

7. The Beidou anti-interference antenna array according to claim 6, characterized in that: The number of the antenna array elements is four, and the four antenna array elements are rotated and arranged and printed on a whole PCB board.

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