Substrate integrated waveguide feed double-frequency vortex field metasurface antenna device and method

Abstract

The invention discloses a substrate integrated waveguide feed double-frequency vortex field metasurface antenna device and method, a first power divider is connected with a transmitter through an SMA joint and a coaxial line, the transmitter provides an excitation signal, and the antenna structure is fed with the first power divider, a first band elimination filter and a second band elimination filter. Therefore, excitation and emission of OAM vortex electromagnetic waves are realized. When an excitation signal passes through the first power divider, one-to-two equal-amplitude in-phase power division is realized; when an excitation signal passes through the first band elimination filter connected with the inner loop antenna, a frequency band signal near the working frequency of the outer loop antenna is filtered out, so that a signal of the working frequency of the inner loop antenna is normally transmitted to the inner loop antenna through the first band elimination filter; when the excitation signal passes through the second band elimination filter connected with the outer loop antenna, a frequency band signal near the working frequency of the inner loop antenna is filtered, so that the signal of the working frequency of the outer loop antenna is normally transmitted to the outer loop antenna through the second band elimination filter.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave antennas, and in particular to a substrate-integrated waveguide-fed dual-frequency vortex field metasurface antenna device and method. Background Art

[0002] As the frequency increases, the transmission loss of the antenna becomes more and more serious. Although the traditional microstrip structure is simple and easy to integrate with external circuits, its transmission loss is large at higher frequencies such as microwaves and millimeter waves. Although the traditional metal waveguide has low loss, it is large in size and not easy to integrate with external circuits.

[0003] In the prior art, a Chinese invention patent, patent publication number CN116365251A, patent name: A millimeter-wave dual-frequency circularly polarized metasurface antenna based on substrate integrated waveguide feeding, discloses a millimeter-wave dual-frequency circularly polarized metasurface antenna based on substrate integrated waveguide feeding, including a metasurface with irregular units in some units and a SIW dual-frequency T-shaped slot antenna, the metasurface with irregular units in some units is composed of a first dielectric substrate and a metasurface layer, the metasurface layer is arranged on the front of the first dielectric substrate, including 13 square units of the same size, which are arranged periodically; the SIW dual-frequency T-shaped slot antenna includes a second dielectric substrate, and the second dielectric substrate is provided with a first metallized through hole, a second metallized through hole, and a third metallized through hole penetrating the second upper metal coating, the second dielectric substrate and the second lower metal coating, and the second upper metal coating is etched with a T-shaped coupling slot.

[0004] The inventors have found that the prior art has the following technical problems: the existing microwave millimeter wave substrate integrated waveguide antenna has an electric wall structure that relies on drilled metal through holes, which is easy to deform when the frequency increases, resulting in low reliability and low gain. Summary of the invention

[0005] In order to solve the deficiencies of the prior art, the present invention provides a substrate-integrated waveguide-fed dual-frequency vortex field metasurface antenna device and method; it relates to an on-chip integrated dual-frequency vortex field antenna suitable for high-speed communication equipment and substrate-integrated waveguide antennas, which can be realized through coplanar metasurface technology at low cost, miniaturization, and without through holes. A substrate-integrated waveguide dual-frequency vortex field antenna is realized through coplanar metasurface technology at low cost, miniaturization, and without through holes.

[0006] On the one hand, a substrate-integrated waveguide-fed dual-frequency vortex field metasurface antenna device is provided, comprising: a dual-frequency antenna, the dual-frequency antenna comprising: a first top layer, a first middle layer and a first bottom layer arranged in sequence from top to bottom; the first top layer comprises: an inner ring and an outer ring, the inner ring and the outer ring have the same center, the inner ring and the outer ring have different radii, wherein the radius of the inner ring is smaller than the radius of the outer ring; the inner ring and the outer ring are both three-quarters of a circumference; the inner ring is provided with two ends, namely a first end and a second end, and the outer ring is provided with two ends, namely a third end and a fourth end;

[0007] The first end is connected to the first end of the first power divider through the first tapered gradient conversion structure and the first band-stop filter in sequence; the third end is connected to the second end of the first power divider through the second tapered gradient conversion structure and the second band-stop filter in sequence;

[0008] The second end is connected to the first end of the second power divider through a third conical gradient transition structure and a third band-stop filter in sequence; the fourth end is connected to the second end of the second power divider through a fourth conical gradient transition structure and a fourth band-stop filter in sequence; the third end of the first power divider is used to transmit signals, and the third end of the second power divider is used to receive signals.

[0009] On the other hand, a working method of a substrate-integrated waveguide-fed dual-frequency vortex field metasurface antenna device is provided, comprising:

[0010] The first power divider is connected to the transmitter through an SMA connector and a coaxial line, and an excitation signal is provided through the transmitter to realize feeding of the antenna structure with the first power divider, the first band-stop filter, and the second band-stop filter, thereby realizing excitation and emission of OAM vortex electromagnetic waves;

[0011] When the excitation signal passes through the first power divider, equal amplitude and in-phase power division of one into two is achieved;

[0012] When the excitation signal passes through the first band-stop filter connected to the inner loop antenna, the frequency band signal near the working frequency of the outer loop antenna is filtered out, so the signal of the working frequency of the inner loop antenna passes through the first band-stop filter normally and is transmitted to the inner loop antenna;

[0013] When the excitation signal passes through the second band-stop filter connected to the outer loop antenna, the frequency band signal near the working frequency of the inner loop antenna is filtered out, so the signal of the working frequency of the outer loop antenna passes through the second band-stop filter normally and is transmitted to the outer loop antenna.

[0014] The above technical solution has the following advantages or beneficial effects:

[0015] In view of the limitations of traditional antennas in terms of miniaturization and integration, the present invention proposes a design of a substrate-integrated waveguide miniaturized antenna based on a coplanar metasurface. The diamond coplanar metasurface replaces the metal through-holes, avoiding the drilling process and greatly improving the reliability. The trapezoidal coplanar metasurface replaces the traditional long strip gaps to achieve precise control of vortex waves. The antenna has the characteristics of high integration, small size, high reliability, high gain, etc., and can effectively improve the performance of the communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings in the specification, which constitute a part of the present invention, are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0017] Figure 1 is a schematic cross-sectional diagram of the antenna structure of Embodiment 1;

[0018] Figure 2 is a top view of the antenna structure of Embodiment 1;

[0019] Figure 3 is a top view of the T-shaped power divider of the first embodiment;

[0020] Figure 4 is a top view of the band-stop filter of Embodiment 1;

[0021] Figure 5 This is an overall schematic diagram of the first embodiment (antenna+band-stop filter+power divider);

[0022] Figure 6 is a structural diagram of the first super surface unit of Example 1;

[0023] Figure 7 is a structural diagram of a second super-surface unit in Embodiment 1;

[0024] Figure 8 This is a simulation result diagram of S11 of Example 1;

[0025] Fig. 9 This is the outer ring radiation pattern of Embodiment 1;

[0026] Fig.10 The inner ring radiation pattern of the first embodiment;

[0027] Fig.11 It is a schematic diagram of a metal shielding box of Embodiment 1;

[0028] Among them, 1, the first rectangular patch, 2, the second rectangular patch, 3, the third rectangular patch, 4, the fourth rectangular patch, 5, the fifth rectangular patch, 6, the sixth rectangular patch, 7, the seventh rectangular patch, 8, the eighth rectangular patch, 9, the ninth rectangular patch, 10, the tenth rectangular patch, 11, the eleventh rectangular patch, 12, the twelfth rectangular patch, 13, the thirteenth rectangular patch. DETAILED DESCRIPTION

[0029] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present invention belongs.

[0030] Embodiment 1

[0031] like Figure 1 As shown, the present embodiment provides a substrate-integrated waveguide-fed dual-frequency vortex field metasurface antenna device, comprising: a dual-frequency antenna, the dual-frequency antenna comprising: a first top layer, a first middle layer and a first bottom layer arranged in sequence from top to bottom; the first top layer comprises: an inner ring and an outer ring, the inner ring and the outer ring have the same center, the inner ring and the outer ring have different radii, wherein the radius of the inner ring is smaller than the radius of the outer ring; the inner ring and the outer ring are both three-quarters of a circle; the inner ring is provided with two ends, namely a first end and a second end, and the outer ring is provided with two ends, namely a third end and a fourth end;

[0032] The first end is connected to the first end of the first power divider through the first tapered gradient conversion structure and the first band-stop filter in sequence; the third end is connected to the second end of the first power divider through the second tapered gradient conversion structure and the second band-stop filter in sequence;

[0033] The second end is connected to the first end of the second power divider through a third conical gradient transition structure and a third band-stop filter in sequence; the fourth end is connected to the second end of the second power divider through a fourth conical gradient transition structure and a fourth band-stop filter in sequence; the third end of the first power divider is used to transmit signals, and the third end of the second power divider is used to receive signals.

[0034] Furthermore, both inner and outer edges of the inner ring are provided with double rows of diamond holes, and both inner and outer edges of the outer ring are provided with double rows of diamond holes; the double rows of diamond holes are two rows of diamond holes; the diamond holes refer to a diamond structure with a solid middle and hollow edges; among the four corners of the diamond holes, one corner is non-hollow, and the other three corners are hollow; the non-hollow corner serves as the opening direction of the diamond hole.

[0035] Furthermore, a group of gaps is arranged at a set interval on the inner ring from the first end to the second end; each group of gaps is provided with three sub-gaps of increasing lengths in sequence.

[0036] Furthermore, a group of gaps is arranged at a set interval on the outer ring from the third end to the fourth end; each group of gaps is provided with three sub-gaps with increasing lengths in sequence.

[0037] Furthermore, the inner ring and the outer ring are both metal patches.

[0038] Furthermore, the first intermediate layer is a dielectric; the dielectric refers to a material with electrical properties, used to form a substrate material or a dielectric layer of a printed circuit board (PCB), and is processed by a standard PCB manufacturing process. The first intermediate layer is configured to hollow out the area between the inner ring and the outer ring.

[0039] Furthermore, the first bottom layer is a radiant floor, which is also provided with diamond holes. The positions of the diamond holes of the radiant floor correspond one to one with the positions of the diamond holes of the first top layer, but the opening directions of the diamond holes are opposite to the opening directions of the diamond holes of the first top layer.

[0040] The radiant floor refers to a large area of ​​copper foil connected to the ground and designed on the PCB, which is used to achieve signal transmission and grounding. The copper foil is usually achieved by laying a layer of copper on the dielectric material through physical or chemical methods (such as electroplating, deposition, etc.).

[0041] Furthermore, each group of gaps is provided with three sub-gaps of increasing lengths. Assuming that the three sub-gaps are the first sub-gaps, the second sub-gaps and the third sub-gaps, the length of the first sub-gaps is smaller than the length of the second sub-gaps, and the length of the second sub-gaps is smaller than the length of the third sub-gaps.

[0042] Further, the first end of the first sub-slot is connected to the first end of the second sub-slot to obtain a first line segment; the first end of the second sub-slot connected to the first end of the first sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the first end of the first sub-slot;

[0043] The second end of the first sub-slot is connected to the second end of the second sub-slot to obtain a second line segment; the second end of the second sub-slot connected to the second end of the first sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the second end of the first sub-slot;

[0044] The first end of the third sub-slot is connected to the first end of the second sub-slot to obtain a third line segment; the first end of the second sub-slot connected to the first end of the third sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the first end of the third sub-slot;

[0045] The second end of the third sub-slot is connected to the second end of the second sub-slot to obtain a fourth line segment; the second end of the second sub-slot connected to the second end of the third sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the second end of the third sub-slot;

[0046] The first line segment, the second line segment, the third line segment, the fourth line segment, the longitudinal center axis of the first sub-slot and the longitudinal center axis of the third sub-slot together form a trapezoid.

[0047] Furthermore, the first, second and third sub-slots are all in the shape of rectangles.

[0048] Furthermore, the first band-stop filter, the second band-stop filter, the third band-stop filter, the fourth band-stop filter, the first power divider, the second power divider and the dual-frequency antenna are all located in the same plane.

[0049] Furthermore, the internal structure of the first power divider is the same as that of the second power divider. The first power divider includes: a second top layer, a second middle layer and a second bottom layer arranged in sequence from top to bottom; the second top layer is a metal microstrip line, the second middle layer is a dielectric, and the second bottom layer is a radiation floor.

[0050] Furthermore, if Figure 3 As shown, the second top layer includes: a first rectangular patch 1, a second rectangular patch 2, a third rectangular patch 3, a fourth rectangular patch 4, a fifth rectangular patch 5 and a sixth rectangular patch 6;

[0051] Wherein, the first end of the first rectangular patch 1 is the first end of the first power divider;

[0052] The second end of the first rectangular patch 1 is connected to the first end of the second rectangular patch 2;

[0053] The second end of the second rectangular patch 2 is connected to the first end of the third rectangular patch 3;

[0054] The second end of the third rectangular patch 3 is connected to the first end of the fourth rectangular patch 4;

[0055] The second end of the fourth rectangular patch 4 is the second end of the first power divider;

[0056] The second end of the second rectangular patch 2 and the first end of the third rectangular patch 3 are both connected to the first end of the fifth rectangular patch 5, and the second end of the fifth rectangular patch 5 is connected to the first end of the sixth rectangular patch 6; the second end of the sixth rectangular patch 6 is the third end of the first power divider.

[0057] Further, the longitudinal center axis of the first rectangular patch 1 and the longitudinal center axis of the second rectangular patch 2 are perpendicular to each other;

[0058] The longitudinal center axis of the second rectangular patch 2 is in a straight line with the longitudinal center axis of the third rectangular patch 3;

[0059] The longitudinal center axis of the third rectangular patch 3 and the longitudinal center axis of the fourth rectangular patch 4 are perpendicular to each other;

[0060] The longitudinal center axis of the third rectangular patch 3 and the longitudinal center axis of the fifth rectangular patch 5 are perpendicular to each other;

[0061] The longitudinal center axis of the fifth rectangular patch 5 and the longitudinal center axis of the sixth rectangular patch 6 are in a straight line.

[0062] It should be understood that the second, third, fifth and sixth rectangular patches together form a "T"-shaped structure.

[0063] It should be understood that the first, second, third, fourth, fifth and sixth rectangular patches are all implemented by microstrip lines.

[0064] It should be understood that the first power divider is configured in the above manner in order to achieve equal-amplitude and in-phase power division of the RF excitation signal into two, and to excite the inner loop antenna and the outer loop antenna respectively.

[0065] Furthermore, the first band-stop filter, the second band-stop filter, the third band-stop filter and the fourth band-stop filter have the same internal structure.

[0066] Furthermore, the first band-stop filter comprises: a third top layer, a third middle layer and a third bottom layer arranged in sequence from top to bottom; the third top layer is a metal microstrip line; the third middle layer is a dielectric; and the third bottom layer is a radiation floor.

[0067] The metal microstrip line refers to: a copper-clad structure designed on a PCB for signal transmission;

[0068] The medium refers to: a material with specific electrical properties, mainly used to form a substrate material or dielectric layer of a printed circuit board (PCB);

[0069] The radiant floor refers to: one or more layers of large-area copper foil connected to the ground designed on the PCB, which is used to achieve signal transmission and grounding.

[0070] Further, the third top layer comprises: a seventh rectangular patch 7;

[0071] The longitudinal center axis of the seventh rectangular patch 7 is arranged in the middle of the third top layer;

[0072] The eighth rectangular patch 8, the ninth rectangular patch 9, the tenth rectangular patch 10 and the eleventh rectangular patch 11 are arranged on one side of the longitudinal center axis of the seventh rectangular patch;

[0073] The twelfth rectangular patch 12 and the thirteenth rectangular patch 13 are arranged on the other side of the longitudinal center axis of the seventh rectangular patch;

[0074] Among them, the longitudinal center axis of the eighth rectangular patch 8 is perpendicular to the longitudinal center axis of the ninth rectangular patch 9; the longitudinal center axis of the tenth rectangular patch 10 is perpendicular to the longitudinal center axis of the eleventh rectangular patch 11; the longitudinal center axis of the twelfth rectangular patch 12 is perpendicular to the longitudinal center axis of the thirteenth rectangular patch 13;

[0075] Among them, there is a gap between the eighth rectangular patch and the seventh rectangular patch; there is a gap between the ninth rectangular patch and the seventh rectangular patch; there is a gap between the tenth rectangular patch and the seventh rectangular patch; there is a gap between the eleventh rectangular patch and the seventh rectangular patch; there is a gap between the twelfth rectangular patch and the seventh rectangular patch; there is a gap between the thirteenth rectangular patch and the seventh rectangular patch;

[0076] One end of the eighth rectangular patch is connected to one end of the ninth rectangular patch; one end of the tenth rectangular patch is connected to one end of the eleventh rectangular patch; one end of the twelfth rectangular patch is connected to one end of the thirteenth rectangular patch.

[0077] One end of the seventh rectangular patch 7 is one end of the first band-stop filter; the other end of the seventh rectangular patch 7 is the other end of the first band-stop filter.

[0078] Furthermore, the seventh, eighth, ninth, tenth, eleventh, twelfth and thirteenth rectangular patches are all metal microstrip lines or metal patches.

[0079] It should be understood that the band-stop filter is configured in the above manner in order to filter out the frequency band signal near the operating frequency of the outer (inner) ring antenna when the excitation signal passes through the band-stop filter connected to the inner (outer) ring antenna. Therefore, the signal of the operating frequency of the inner (outer) ring antenna passes through the filter normally and is transmitted to the inner (outer) ring antenna. This structural design can avoid crosstalk between different operating frequencies of the inner and outer rings, improve anti-interference ability, and improve signal integrity.

[0080] Furthermore, the first tapered gradual conversion structure, the second tapered gradual conversion structure, the third tapered gradual conversion structure and the fourth tapered gradual conversion structure have the same internal structure, and the first tapered gradual conversion structure comprises:

[0081] The conical axis section and the rectangular surface are connected in sequence; the top of the conical axis section is connected to one end of the rectangular surface, and the other end of the rectangular surface is connected to the first band-stop filter; the bottom of the conical axis section is connected to the dual-frequency antenna.

[0082] Furthermore, the conical axis section and the rectangular surface are both metal patches.

[0083] Furthermore, the first conical gradient conversion structure, the second conical gradient conversion structure, the third conical gradient conversion structure and the fourth conical gradient conversion structure are located in the same plane as the dual-band antenna.

[0084] Furthermore, the device also includes: Fig.11 As shown, a first metal shielding box and a second metal shielding box; the shape of the first metal shielding box is the same as that of the second metal shielding box; the first metal shielding box is provided with a first cuboid, a second cuboid and a third cuboid, the interior of the first cuboid is a hollow structure; the left and right ends of the second cuboid are open and the interior is a hollow structure; the left and right ends of the third cuboid are open and the interior is a hollow structure; the first, second and third cuboids do not have a bottom surface; the central axis of the first cuboid is perpendicular to the central axis of the second cuboid; the central axis of the first cuboid is perpendicular to the central axis of the third cuboid; one end of the second cuboid is connected to the first end of the first cuboid; one end of the third cuboid is connected to the second end of the second cuboid; the interior of the connection between the second cuboid and the first cuboid is connected; the interior of the connection between the third cuboid and the first cuboid is connected; the first metal shielding box is covered on the first power divider, the first band stop filter and the second band stop filter; the second metal shielding box is covered on the second power divider, the third band stop filter and the fourth band stop filter.

[0085] The top-view shapes of the first metal shielding box and the second metal shielding box are the same in size and shape as the dielectric material occupied by the T-shaped power divider and the band-stop filter, and have a certain suspended height.

[0086] The first metal shielding box and the second metal shielding box are located above the two T-shaped power divider feeding ends, ie, the third end portions. Sides of the first metal shielding box and the second metal shielding box have reserved openings for connecting to SMA connectors.

[0087] The first end of the first metal shielding box is arranged at an end where the first tapered gradient conversion structure is connected to the first band-stop filter;

[0088] The second end of the first metal shielding box is arranged at an end where the second tapered gradient conversion structure is connected to the second band-stop filter;

[0089] The first end of the second metal shielding box is arranged at an end where the third tapered gradient conversion structure is connected to the third band-stop filter;

[0090] The second end of the second metal shielding box is arranged at an end where the fourth tapered gradient conversion structure is connected to the fourth band-stop filter;

[0091] The first end of the first metal shielding box, the second end of the first metal shielding box, the first end of the second metal shielding box and the side surfaces of the second end of the second metal shielding box are all provided with reserved openings for the microstrip transmission line to pass through.

[0092] The metal shielding box is made of metal, and its sides except for the reserved opening are electrically connected to the radiation floor, and has a relatively thin thickness (a typical embodiment may be 0.13 mm).

[0093] The dual-band antenna is a concentric circle structure with two substrate-integrated waveguides of different radii and 3 / 4 of the circumference. Each waveguide is responsible for a different working frequency band, and is provided with a top layer, a middle layer, and a bottom layer. The top layer is the radiation layer, which is provided with a metal patch, a rhombus coplanar metasurface to replace the through hole, and a trapezoidal coplanar metasurface to form a leaky wave gap. The middle layer is a dielectric, and the bottom layer is a radiation floor. The radiation floor is also provided with a rhombus coplanar metasurface to replace the through hole. The band-stop filter and the power divider are located in the same plane as the dual-band antenna. The top layer is a metal microstrip line to form a signal transmission layer, the middle layer is a dielectric, and the bottom layer is a radiation floor. The feature is the use of metasurface technology to achieve low-cost, miniaturized on-chip integration without through holes, and the excitation of dual-frequency vortex electromagnetic wave radiation. It is suitable for many types of miniaturized communication equipment, providing high-gain radiation performance and stable vortex beams.

[0094] The present invention generates dual-frequency vortex waves of 8.2 GHz and 12 GHz, both of which have mode l=1.

[0095] The operating frequency of the outer ring antenna is 8.2 GHz. By setting multiple groups of trapezoidal metasurface leaky wave slots on the circular antenna structure, the 8.2 GHz radio frequency signal is radiated outward through the leaky wave structure, and each group of leaky wave slots achieves phase delay, and finally achieves a phase change of approximately 360 degrees on the circumference, thereby realizing a vortex wave with mode l=1 and an operating frequency of 8.2 GHz.

[0096] Similarly, the operating frequency of the inner loop antenna is 12 GHz. By setting multiple groups of trapezoidal metasurface leaky wave slots on the circular antenna structure, the 12 GHz RF signal is radiated outward through the leaky wave structure, and each group of leaky wave slots achieves phase delay, and finally achieves a phase change of approximately 360 degrees on the circle, thereby realizing a vortex wave with mode l=1 and an operating frequency of 12 GHz.

[0097] Therefore, the present invention uses a diamond-shaped coplanar metasurface to replace the through hole, avoiding the drilling process and only using the etching process, which greatly improves the reliability.

[0098] like Figure 1 As shown in the figure, the SIW is bent into a 3 / 4 circle, and a trapezoidal coplanar metasurface is proposed to replace the traditional long strip gap, and a circle of specific phase superposition is realized, that is, OAM vortex electromagnetic wave. Two 3 / 4 circles, one large and one small, are used to realize two working frequencies, that is, dual-frequency antenna design. Then, a band-stop filter and a power divider are added to realize the construction of the feeding network. Finally, a metal shielding box is added to the feeding part to enhance the shielding performance and improve the signal integrity. The antenna part includes two 3 / 4 circular substrate integrated waveguide sub-antennas, and the two sub-antennas are responsible for one working frequency band respectively. Each 3 / 4 circular ring is transformed from a classic substrate integrated waveguide leaky wave antenna, and the metal through hole of the traditional design is replaced by an integrated diamond coplanar metasurface. The antenna is bent into a ring, and another leaky wave gap of a trapezoidal coplanar metasurface is etched to replace the traditional single long strip, so as to realize the specific phase radiation of the circular distribution, thereby realizing the excitation of vortex electromagnetic waves.

[0099] like Figure 2 As shown, it is a top view. The blue is the dielectric material, Rogers RO4350B, which is a commonly used high-frequency circuit board substrate. Its dielectric constant is very stable in a wide frequency range. It also has low loss, low thermal expansion coefficient and excellent mechanical properties. Its relative dielectric constant is 3.48 and its thickness is 0.762mm. The gray is the metal radiation layer. It can be seen that the two SIWs are bent into 3 / 4 circles with different radii. The end is a tapered gradient conversion structure.

[0100] The antenna uses two types of coplanar metasurfaces: a rhombus coplanar metasurface and a trapezoidal coplanar metasurface;

[0101] 1. Rhombus coplanar metasurfaces, such as Figure 6 As shown, the double-layer structure, the first layer is etched on the upper surface of the substrate integrated waveguide, which is a hollow open diamond structure, and the second layer is etched on the lower surface of the substrate integrated waveguide, which is also a hollow open diamond structure, but the opening direction is opposite to the first layer, that is, the diamond structure on the lower surface of the substrate integrated waveguide is rotated 180 degrees around its own center on the horizontal plane coplanar with the diamond structure on the upper surface. The dielectric layer of the substrate integrated waveguide is filled in the middle.

[0102] The role of the diamond coplanar metasurface is to replace the metal vias, which are located in the reserved positions of the vias in the traditional design of substrate integrated waveguide. Each SIW has two rows on both sides of the edge, and each side uses two rows.

[0103] like Figure 6 As shown, a schematic diagram of the opening is opposite: it can be seen that the "opening" of the upper layer with a width of g1 is on the front side, and the lower layer is twisted 180 degrees, and the "opening" is on the back side.

[0104] Of course, the "hollow type" metasurface used here is hollow, so the "diamond" is hollow, and the opening is "solid" metal (the metal is gray in the picture and the hollow is transparent).

[0105] 2. Trapezoidal coplanar hypersurfaces, such as Figure 7 As shown, a single-layer structure is etched on the upper surface of the substrate integrated waveguide, which is three hollowed-out parallel slits with an arithmetic progression of spacing.

[0106] The role of the trapezoidal coplanar metasurface is to replace the single-slit simple slot of the substrate integrated waveguide antenna, and is located at the slot reserved position (the most central) in the traditional design.

[0107] There are two ends in the inner and outer rings, one SMA feeds power through the feeding network, and the other SMA receives the residual wave. Figure 3 As shown in the figure. Since the inner and outer loops of the introduced power divider have different operating frequency bands, in order to avoid mutual interference, a filter needs to be inserted between the power divider and the antenna to reduce interference. The design here is a band-stop filter, such as Figure 4 shown.

[0108] The power divider is responsible for transmitting the electromagnetic waves fed by a single end to the inner and outer ring antennas, and is connected to the antennas through a band-stop filter. The band-stop filter is responsible for filtering out the set frequency of the other branch to ensure that the signal of the set frequency of the current branch passes normally. Figure 3 As shown, it is a T-shaped power divider, the lower end of which is connected to the SMA interface, and the upper end realizes 1-to-2 division, which is sent to the inner ring and the outer ring respectively.

[0109] Each filter can filter out interference. In the present invention, a band-stop filter is used to achieve better notch performance and minimize interference to the antenna. The inner loop operates at 12 GHz, and the band-stop filter needs to specifically filter out 8.2 GHz, where the notch is. The outer loop operates at 8.2 GHz, and the band-stop filter needs to specifically filter out 12 GHz, where the notch is. In this way, the inner and outer loops will not affect each other, and the signals from the feed end (8.2 GHz and 12 GHz) can reach their respective loops normally.

[0110] like Figure 4 As shown in the figure, the internal structure of the band-stop filter; Figure 5 As shown in the figure, the overall diagram (antenna + band-stop filter + power divider); Figure 8 As shown in the S11 result diagram of the antenna, the S11 values ​​corresponding to the two operating frequencies of 8.2GHz and 12GHz are -11.23dB and -13.06dB, which are less than -10dB and meet the requirements; Fig. 9 As shown, the outer ring radiation pattern is Fig.10 As shown, the inner ring radiation pattern.

[0111] Embodiment 2

[0112] This embodiment provides a working method of a substrate-integrated waveguide-fed dual-frequency vortex field metasurface antenna device, including:

[0113] The first power divider is connected to the transmitter through an SMA connector and a coaxial line, and an excitation signal is provided through the transmitter to realize feeding of the antenna structure with the first power divider, the first band-stop filter, and the second band-stop filter, thereby realizing excitation and emission of OAM vortex electromagnetic waves;

[0114] When the excitation signal passes through the first power divider, equal amplitude and in-phase power division of one into two is achieved;

[0115] When the excitation signal passes through the first band-stop filter connected to the inner loop antenna, the frequency band signal near the working frequency of the outer loop antenna is filtered out, so the signal of the working frequency of the inner loop antenna passes through the first band-stop filter normally and is transmitted to the inner loop antenna;

[0116] When the excitation signal passes through the second band-stop filter connected to the outer loop antenna, the frequency band signal near the working frequency of the inner loop antenna is filtered out, so the signal of the working frequency of the outer loop antenna passes through the second band-stop filter normally and is transmitted to the outer loop antenna.

[0117] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A dual-frequency vortex field metasurface antenna device with substrate integrated waveguide feeding, characterized in that: include: A dual-frequency antenna, the dual-frequency antenna comprising: a first top layer, a first middle layer and a first bottom layer arranged in order from top to bottom; the first top layer comprises: an inner ring and an outer ring, the inner ring and the outer ring have the same center, the inner ring and the outer ring have different radii, wherein the radius of the inner ring is smaller than the radius of the outer ring; the inner ring and the outer ring are both three-quarters of a circle; the inner ring is provided with two ends, namely a first end and a second end, and the outer ring is provided with two ends, namely a third end and a fourth end; The first end is connected to the first end of the first power divider through the first tapered gradient conversion structure and the first band-stop filter in sequence; the third end is connected to the second end of the first power divider through the second tapered gradient conversion structure and the second band-stop filter in sequence; The second end is connected to the first end of the second power divider through a third conical gradient transition structure and a third band-stop filter in sequence; the fourth end is connected to the second end of the second power divider through a fourth conical gradient transition structure and a fourth band-stop filter in sequence; the third end of the first power divider is used to transmit signals, and the third end of the second power divider is used to receive signals.

2. The substrate-integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 1, characterized in that: The inner and outer edges of the inner ring are both provided with double rows of diamond holes, and the inner and outer edges of the outer ring are both provided with double rows of diamond holes; the double rows of diamond holes are two rows of diamond holes; the diamond holes refer to a diamond structure with a solid center and hollow edges; among the four corners of the diamond holes, one corner is non-hollow, and the other three corners are hollow; the non-hollow corner serves as the opening direction of the diamond hole; The first bottom layer is a radiant floor, which is also provided with diamond holes. The positions of the diamond holes of the radiant floor correspond to the positions of the diamond holes of the first top layer, and the opening directions of the diamond holes are opposite to the opening directions of the diamond holes of the first top layer.

3. The substrate integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 1, characterized in that: A group of gaps is arranged at a set interval on the inner ring from the first end to the second end; each group of gaps is provided with three sub-gaps of increasing lengths in sequence; A group of gaps is arranged at a set interval on the outer ring from the third end to the fourth end; each group of gaps is provided with three sub-gaps with increasing lengths in sequence.

4. The substrate integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 3, characterized in that: Each group of slits is provided with three sub-slits of increasing lengths. Assuming that the three sub-slits are respectively a first sub-slit, a second sub-slit and a third sub-slit, the length of the first sub-slit is smaller than the length of the second sub-slit, and the length of the second sub-slit is smaller than the length of the third sub-slit; The first end of the first sub-slot is connected to the first end of the second sub-slot to obtain a first line segment; the first end of the second sub-slot connected to the first end of the first sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the first end of the first sub-slot; The second end of the first sub-slot is connected to the second end of the second sub-slot to obtain a second line segment; the second end of the second sub-slot connected to the second end of the first sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the second end of the first sub-slot; The first end of the third sub-slot is connected to the first end of the second sub-slot to obtain a third line segment; the first end of the second sub-slot connected to the first end of the third sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the first end of the third sub-slot; The second end of the third sub-slot is connected to the second end of the second sub-slot to obtain a fourth line segment; the second end of the second sub-slot connected to the second end of the third sub-slot refers to: the end of the two ends of the second sub-slot that is closest to the second end of the third sub-slot; The first line segment, the second line segment, the third line segment, the fourth line segment, the longitudinal center axis of the first sub-slot and the longitudinal center axis of the third sub-slot together form a trapezoid.

5. The substrate integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 1, characterized in that: The internal structures of the first power divider and the second power divider are the same. The first power divider includes: a second top layer, a second middle layer and a second bottom layer arranged in sequence from top to bottom; the second top layer is a metal microstrip line, the second middle layer is a dielectric, and the second bottom layer is a radiation floor; The second top layer includes: a first rectangular patch, a second rectangular patch, a third rectangular patch, a fourth rectangular patch, a fifth rectangular patch and a sixth rectangular patch; The first end of the first rectangular patch is the first end of the first power divider; the second end of the first rectangular patch is connected to the first end of the second rectangular patch; the second end of the second rectangular patch is connected to the first end of the third rectangular patch; the second end of the third rectangular patch is connected to the first end of the fourth rectangular patch; the second end of the fourth rectangular patch is the second end of the first power divider; The second end of the second rectangular patch and the first end of the third rectangular patch are both connected to the first end of the fifth rectangular patch, and the second end of the fifth rectangular patch is connected to the first end of the sixth rectangular patch; the second end of the sixth rectangular patch is the third end of the first power divider; The longitudinal center axis of the first rectangular patch and the longitudinal center axis of the second rectangular patch are perpendicular to each other; The longitudinal center axis of the second rectangular patch is in a straight line with the longitudinal center axis of the third rectangular patch; The longitudinal center axis of the third rectangular patch is perpendicular to the longitudinal center axis of the fourth rectangular patch; the longitudinal center axis of the third rectangular patch is perpendicular to the longitudinal center axis of the fifth rectangular patch; the longitudinal center axis of the fifth rectangular patch is in a straight line with the longitudinal center axis of the sixth rectangular patch.

6. The substrate integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 1, characterized in that: The first band-stop filter, the second band-stop filter, the third band-stop filter and the fourth band-stop filter have the same internal structure; the first band-stop filter comprises: a third top layer, a third middle layer and a third bottom layer arranged in sequence from top to bottom; the third top layer is a metal microstrip line; the third middle layer is a dielectric; the third bottom layer is a radiation floor; the third top layer comprises: a seventh rectangular patch; the longitudinal center axis of the seventh rectangular patch is arranged in the middle position of the third top layer; The eighth rectangular patch, the ninth rectangular patch, the tenth rectangular patch and the eleventh rectangular patch are arranged on one side of the longitudinal center axis of the seventh rectangular patch; The twelfth rectangular patch and the thirteenth rectangular patch are arranged on the other side of the longitudinal center axis of the seventh rectangular patch; Among them, the longitudinal center axis of the eighth rectangular patch is perpendicular to the longitudinal center axis of the ninth rectangular patch; the longitudinal center axis of the tenth rectangular patch is perpendicular to the longitudinal center axis of the eleventh rectangular patch; the longitudinal center axis of the twelfth rectangular patch is perpendicular to the longitudinal center axis of the thirteenth rectangular patch; Among them, there is a gap between the eighth rectangular patch and the seventh rectangular patch; there is a gap between the ninth rectangular patch and the seventh rectangular patch; there is a gap between the tenth rectangular patch and the seventh rectangular patch; there is a gap between the eleventh rectangular patch and the seventh rectangular patch; there is a gap between the twelfth rectangular patch and the seventh rectangular patch; there is a gap between the thirteenth rectangular patch and the seventh rectangular patch; One end of the eighth rectangular patch is connected to one end of the ninth rectangular patch; one end of the tenth rectangular patch is connected to one end of the eleventh rectangular patch; one end of the twelfth rectangular patch is connected to one end of the thirteenth rectangular patch.

7. The substrate integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 1, characterized in that: The first tapered gradual conversion structure, the second tapered gradual conversion structure, the third tapered gradual conversion structure and the fourth tapered gradual conversion structure have the same internal structure. The first tapered gradual conversion structure includes: The conical axis section and the rectangular surface are connected in sequence; the top of the conical axis section is connected to one end of the rectangular surface, and the other end of the rectangular surface is connected to the first band-stop filter; the bottom of the conical axis section is connected to the dual-frequency antenna.

8. The substrate integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 1, characterized in that: The device also includes: a first metal shielding box and a second metal shielding box; the shape of the first metal shielding box is the same as that of the second metal shielding box; the first metal shielding box is provided with a first cuboid, a second cuboid and a third cuboid, the interior of the first cuboid is a hollow structure; the left and right ends of the second cuboid are open and the interior is a hollow structure; the left and right ends of the third cuboid are open and the interior is a hollow structure; the first, second and third cuboids do not have a bottom surface; the central axis of the first cuboid is perpendicular to the central axis of the second cuboid; the central axis of the first cuboid is perpendicular to the central axis of the third cuboid; one end of the second cuboid is connected to the first end of the first cuboid; one end of the third cuboid is connected to the second end of the second cuboid; the interior of the connection between the second cuboid and the first cuboid is connected; the interior of the connection between the third cuboid and the first cuboid is connected; the first metal shielding box is covered on the first power divider, the first band-stop filter and the second band-stop filter; the second metal shielding box is covered on the second power divider, the third band-stop filter and the fourth band-stop filter.

9. The substrate integrated waveguide-fed dual-frequency vortex field metasurface antenna device according to claim 8, characterized in that: The first end of the first metal shielding box is arranged at an end where the first tapered gradient conversion structure is connected to the first band-stop filter; The second end of the first metal shielding box is arranged at an end where the second tapered gradient conversion structure is connected to the second band-stop filter; The first end of the second metal shielding box is arranged at an end where the third tapered gradient conversion structure is connected to the third band-stop filter; The second end of the second metal shielding box is arranged at an end where the fourth tapered gradient conversion structure is connected to the fourth band-stop filter; The first end of the first metal shielding box, the second end of the first metal shielding box, the first end of the second metal shielding box and the side surfaces of the second end of the second metal shielding box are all provided with reserved openings for the microstrip transmission line to pass through.

10. A working method of a dual-frequency vortex field metasurface antenna device with substrate integrated waveguide feeding, characterized in that: include: The first power divider is connected to the transmitter through an SMA connector and a coaxial line, and an excitation signal is provided through the transmitter to realize feeding of the antenna structure with the first power divider, the first band-stop filter, and the second band-stop filter, thereby realizing excitation and emission of OAM vortex electromagnetic waves; When the excitation signal passes through the first power divider, equal amplitude and in-phase power division of one into two is achieved; When the excitation signal passes through the first band-stop filter connected to the inner loop antenna, the frequency band signal near the working frequency of the outer loop antenna is filtered out, so the signal of the working frequency of the inner loop antenna passes through the first band-stop filter normally and is transmitted to the inner loop antenna; When the excitation signal passes through the second band-stop filter connected to the outer loop antenna, the frequency band signal near the working frequency of the inner loop antenna is filtered out, so the signal of the working frequency of the outer loop antenna passes through the second band-stop filter normally and is transmitted to the outer loop antenna.

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