Broadband circular polarization folding transmission array antenna based on transceiving unit

Abstract

The invention belongs to the technical field of wireless communication, and particularly relates to a broadband circular polarization folding transmission array antenna based on a transceiving unit. The antenna comprises a transmit-receive metasurface, a metal reflection surface and a circular polarization feed source. The transmit-receive metasurface provided by the invention is composed of a plurality of transmit-receive units which are arranged periodically; the circularly polarized feed source provided by the invention adopts SIW feed to excite circularly polarized waves, and the metal reflection surface is integrated on the upper substrate of the circularly polarized feed source. The transmit-receive unit provided by the invention has polarization selection and polarization torsion characteristics, can reflect a left-hand circularly polarized wave incident by a feed source, receives a right-hand circularly polarized electromagnetic wave incident by the feed source, transmits the left-hand circularly polarized wave, and forms a high-gain wave beam in a far-field region through phase compensation and polarization torsion. The antenna has the advantages of low profile (3 / F), circular polarization, high gain and wide bandwidth.

Description

Technical Field

[0001] The present invention belongs to the technical field of wireless communications, and in particular relates to a broadband circularly polarized folded transmission array antenna based on a transceiver unit. Background Art

[0002] With the rapid development of wireless communication technology, especially its widespread application in 5G / 6G communications, satellite communications, radar systems, and other fields, antenna performance requirements are increasing. Traditional antennas such as parabolic antennas and microstrip antennas, while performing well in specific scenarios, have limitations in terms of broadband, low profile, high gain, and circular polarization. Folded transmission array antennas, as a new type of high-performance antenna, combine the advantages of reflective and transmission arrays, offering low profile, lightweight, and conformal properties. They have become a research hotspot in recent years. However, traditional single-polarization antennas are susceptible to multipath interference and polarization mismatch in complex electromagnetic environments, limiting the stability and transmission efficiency of communication systems. In contrast, circularly polarized antennas, due to their insensitivity to polarization mismatch and strong resistance to multipath interference, have become one of the ideal antenna polarization schemes for modern wireless systems. Therefore, broadband circularly polarized folded transmission array antennas can meet the requirements of modern communication systems for wide bandwidth, circularly polarized beams, high gain, and compact structure, and have significant application value.

[0003] In order to further improve the operating frequency band and polarization performance of transmission arrays, a variety of design methods based on folded structures have been proposed. By introducing multi-layer metal structures or coplanar coupling mechanisms, folded transmission arrays can not only increase the equivalent phase delay within a limited size, but also achieve a wider phase coverage range, effectively supporting broadband operation. In terms of achieving circular polarization, the current mainstream methods include the use of crossed dipole structures, rotationally symmetric resonant cavities, double-layer staggered units, loaded bias slot lines, etc. Although these methods perform well in certain frequency bands, they still have bandwidth limitations in high-frequency broadband environments, significant impact on circular polarization purity, and complex multi-layer structures with a large number of layers. Summary of the Invention

[0004] To address the shortcomings of the prior art, the present invention proposes a broadband circularly polarized folded transmission array antenna based on transceiver units. This antenna utilizes a feed system based on a substrate-integrated waveguide (SIW) structure to improve feed efficiency, maintain a stable radiation pattern, and achieve ultra-wideband circular polarization performance. By optimizing the unit array layout and rotational symmetry, circular polarization with controllable beam direction is achieved. Finally, by integrating PCB manufacturing processes, a low-profile, modular, and easily integrated folded transmission array structure is designed.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical solutions:

[0006] A broadband circularly polarized folded transmission array antenna based on a transceiver unit, comprising a transceiver metasurface, a metal reflective surface and a circularly polarized feed stacked from top to bottom; the transceiver metasurface comprises a plurality of periodically arranged transceiver units; the transceiver unit comprises an upper metal patch layer, an upper dielectric substrate layer, an intermediate metal ground layer, an adhesive layer, a lower dielectric substrate layer and a lower metal patch layer stacked from top to bottom; a metal through hole penetrates from the upper metal patch layer to the lower metal patch layer; the circularly polarized feed comprises a 4×4 metasurface unit, an SI reflective surface and a circularly polarized feed stacked from top to bottom W upper dielectric substrate layer, SIW bonding layer, SIW upper metal wall, SIW lower dielectric substrate layer and SIW lower metal wall; the transceiver unit has polarization selection and polarization twisting performance, the left-handed circularly polarized electromagnetic wave output by the circularly polarized feed source can be reflected by the transceiver unit, the reflected left-handed circularly polarized wave is incident on the metal reflective surface and twisted into a right-handed circularly polarized wave, incident on the lower metal patch layer of several transceiver units of the transceiver metasurface, transmitted to the upper metal patch layer through the metal through hole and twisted into a left-handed circularly polarized wave, and the height is reduced to one-third of the focal length by folding the electromagnetic wave.

[0007] Furthermore, as a preferred technical solution of the present invention, the antenna controls 360° phase compensation by rotating the periodically arranged upper metal patch layer. The rotated metal patch is ahead of the non-rotated metal patch in phase, achieving 360° phase coverage without changing the transmission amplitude.

[0008] Furthermore, as a preferred technical solution of the present invention, the upper metal patch layer is a circular patch etched with a U-shaped gap and a diagonal rectangular gap, and a split ring is added around the circular patch to increase the working bandwidth.

[0009] Furthermore, as a preferred technical solution of the present invention, the metal reflective surface is integrated on the SIW upper dielectric substrate layer of the circularly polarized feed.

[0010] Furthermore, as a preferred technical solution of the present invention, the 4×4 metasurface unit of the circularly polarized feed is a square patch, and fan-shaped slots are cut at its diagonal to excite circularly polarized waves, which can achieve a wider bandwidth; a long gap is etched in the center of the metal wall on the SIW to realize energy transmission.

[0011] Furthermore, as a preferred technical solution of the present invention, a pair of symmetrical slots are etched in the metal wall under the SIW of the circularly polarized feed source to realize the conversion of the grounded coplanar waveguide GCPW to SIW, and the GCPW is connected to an external adapter, and then fed to the 4×4 metasurface unit after the GCPW to SIW conversion.

[0012] The broadband circularly polarized folded transmission array antenna based on a transceiver unit described in the present invention, which adopts the above technical solution, has the following technical effects compared with the prior art:

[0013] (1) The circularly polarized feed proposed in the present invention is a planar feed, which reduces the cross section while having a wider impedance bandwidth and axial ratio bandwidth.

[0014] (2) The transceiver unit proposed in the present invention has polarization selection and polarization twisting characteristics, and can reduce the antenna cross-section to one-third of the focal length by folding.

[0015] (3) The broadband circularly polarized folded transmission array antenna based on the transceiver unit proposed in the present invention has a 3dB gain bandwidth of 14.3% and an axial ratio bandwidth of 19%.

[0016] (4) The broadband circularly polarized folded transmission array antenna based on the transceiver unit proposed in the present invention has a small number of layers, a simple structure, is easy to process, and has a low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the three-dimensional structure of an antenna according to an embodiment of the present invention;

[0018] Figure 2 is a schematic diagram of the folding function of the antenna according to an embodiment of the present invention;

[0019] Figure 3 is a top view of the transceiver metasurface of the antenna according to an embodiment of the present invention;

[0020] Figure 4 1 is a schematic diagram of the three-dimensional structure of the transceiver unit of the antenna according to an embodiment of the present invention;

[0021] Figure 5 1. (a) A top view of the upper metal patch layer, (b) A top view of the middle metal ground layer, and (c) A top view of the lower metal patch layer of the antenna according to an embodiment of the present invention;

[0022] Figure 6 is a top view of the circularly polarized feed surface and the metal reflective surface of the antenna according to an embodiment of the present invention;

[0023] Figure 7 Schematic diagram of the three-dimensional structure of the circularly polarized feed and metal reflective surface of the antenna according to an embodiment of the present invention;

[0024] Figure 8 (a) a top view of a 4×4 metasurface unit, (b) a top view of an SIW upper metal wall, and (c) a top view of an SIW lower metal wall of an antenna according to an embodiment of the present invention;

[0025] Figure 91 is a transmission and reflection response diagram of (a) a left-hand circularly polarized wave and (b) a right-hand circularly polarized wave of a transceiver unit of an antenna according to an embodiment of the present invention;

[0026] Figure 10 is the radiation pattern of the circularly polarized feed of the antenna according to the embodiment of the present invention at 27 GHz;

[0027] Figure 11 1 is a performance diagram of the axial ratio of the circularly polarized feed of the antenna according to an embodiment of the present invention varying with frequency;

[0028] Figure 12 is the directional pattern of the antenna of the embodiment of the present invention at 27 GHz;

[0029] Figure 13 is a performance diagram of the gain and axial ratio of the antenna according to the embodiment of the present invention as a function of frequency;

[0030] In the accompanying drawings, 1-transceiver unit; 2-upper metal patch layer; 3-upper dielectric substrate layer; 4-middle metal ground layer; 5-adhesive layer; 6-lower dielectric substrate layer; 7-lower metal patch layer; 8-metal through hole; 9-4×4 metasurface unit; 10-SIW upper dielectric substrate layer; 11-SIW adhesive layer; 12-SIW upper metal wall; 13-SIW lower dielectric substrate layer; 14-SIW lower metal wall; 15-metal reflective surface. DETAILED DESCRIPTION

[0031] The present invention will be further explained below in detail with reference to the accompanying drawings so that those skilled in the art can have a deeper understanding of the present invention and be able to implement it. However, the following reference examples are only used to explain the present invention and are not intended to limit the present invention.

[0032] like Figure 1-8As shown, a broadband circularly polarized folded transmission array antenna based on a transceiver unit includes a transceiver metasurface, a metal reflective surface 15 and a circularly polarized feed stacked from top to bottom; the transceiver metasurface includes a plurality of periodically arranged transceiver units 1; the transceiver unit 1 includes an upper metal patch layer 2, an upper dielectric substrate layer 3, an intermediate metal ground layer 4, an adhesive layer 5, a lower dielectric substrate layer 6, and a lower metal patch layer 7 stacked from top to bottom; a metal through hole 8 passes through the upper metal patch layer 2 to the lower metal patch layer 7; the circularly polarized feed includes a 4×4 metasurface unit 9, an SIW upper layer, and a plurality of metal reflective surface units stacked from top to bottom. The transceiver unit 1 comprises a dielectric substrate layer 10, an SIW bonding layer 11, an SIW upper metal wall 12, an SIW lower dielectric substrate layer 13 and an SIW lower metal wall 14; the transceiver unit 1 has polarization selection and polarization twisting performance, and the left-handed circularly polarized electromagnetic wave output by the circularly polarized feed source can be reflected by the transceiver unit 1. The reflected left-handed circularly polarized wave is incident on the metal reflective surface 15 and twisted into a right-handed circularly polarized wave, which is incident on the lower metal patch layer 7 of several transceiver units 1 of the transceiver metasurface, is transmitted to the upper metal patch layer 2 through the metal through-hole 8 and twisted into a left-handed circularly polarized wave. By folding the electromagnetic wave, the height is reduced to one-third of the focal length.

[0033] like Figure 2 As shown, the circularly polarized feed outputs a left-handed circularly polarized wave, which is incident on the receiving surface of the transceiver metasurface. Due to the polarization selection and polarization conversion characteristics of the transceiver metasurface, the left-handed circularly polarized wave is reflected on the metal reflective surface 15, twisted into a right-handed circularly polarized wave and emitted to the receiving surface. The right-handed circularly polarized wave is received by the receiving surface, transmitted to the transmitting surface through the metal through-hole 8, twisted into a left-handed circularly polarized wave, and after obtaining the corresponding phase compensation, a high-gain beam is formed in the far field.

[0034] The antenna controls 360° phase compensation by rotating the periodically arranged upper metal patch layer 2. The rotated metal patches advance in phase compared to the unrotated ones, achieving 360° phase coverage without changing the transmission amplitude. The upper metal patch layer 2 is a circular patch etched with U-shaped slots and diagonal rectangular slots. Splitting rings are added around the circular patch to increase the operating bandwidth. A metal reflective surface 15 is integrated into the upper dielectric substrate layer 10 of the circularly polarized waveguide (SIW) feed. The 4×4 metasurface elements 9 of the circularly polarized waveguide (CIW) feed are square patches with sector-shaped slots cut into their diagonals to excite circularly polarized waves, achieving a wide bandwidth. The SIW upper metal wall 12 is etched with a long central slot to enable energy transmission. The SIW lower metal wall 14 of the circularly polarized waveguide (CIW) feed is etched with a pair of symmetrical slots to achieve grounded coplanar waveguide (GCPW) to SIW conversion. The GCPW is connected to an external adapter, and after the GCPW-to-SIW conversion, power is fed to the 4×4 metasurface elements 9.

[0035] like Figure 4As shown, the upper dielectric substrate layer 3 and the lower dielectric substrate layer 6 of the transceiver unit 1 are made of the same material and have the same size, and their dielectric constants ε r is [2.2, 6.2], tanδ is 0.0009, height h1 is [0.02λ, 0.1λ], and the dielectric constant ε of the adhesive layer 5 is r is 3.5, tanδ is 0.004, and the height is h2. The material of the metal through hole 8 is pec. In addition, Figure 7 As shown, the dielectric constants ε of the SIW upper dielectric substrate layer 10 and the SIW lower dielectric substrate layer 13 of the circularly polarized feed are r is [2.2, 6.2], tanδ is 0.0009, height h3 is [0.02λ, 0.1λ], and the dielectric constant ε of the SIW bonding layer 11 is r is 3.5, tanδ is 0.004, and the height is h2. Where λ is the free space wavelength.

[0036] The parameters of the antenna in this embodiment are shown in the following table:

[0037] parameter p <![CDATA[r1]]> r2 r3 <![CDATA[h1]]> <![CDATA[h2]]> <![CDATA[d1]]> <![CDATA[d2]]> <![CDATA[a1]]> <![CDATA[a2]]> Value (mm) 5.3 1.4 1.5 1.8 0.762 0.1 0.3 0.6 1.3 1.1 parameter s <![CDATA[w1]]> <![CDATA[l1]]> <![CDATA[r a ]]> sub_a sub_b <![CDATA[f y ]]> <![CDATA[f m ]]> <![CDATA[f x ]]> rr Value (mm) 0.3 0.2 0.4 0.6 1.8 0.1 0.8 1 4.4 0.15 parameter siw_w <![CDATA[h3]]> tapl_1 tapl_2 tapw_1 tapw_2 wg g Value (mm) 4.8 0.508 2.8 2.6 0.4 1.4 0.7 0.1

[0038] like Figure 5 (a)- Figure 5 (c) and Figure 8 (a)- Figure 8 As shown in (c), p is the side length of the dielectric substrate, r1 is the radius of the circular metal patch, r2 is the inner radius of the split ring, r3 is the outer radius of the split ring, h1 is the height of the dielectric substrate, h2 is the height of the adhesive layer, d1 is the diameter of the metal through hole, d2 is the diameter of the circular gap in the floor layer, a1 is the outer side length of the U-shaped gap, a2 is the inner side length of the U-shaped gap, s is the distance the metal patch is offset in the xoy direction relative to the metal through hole, w1 is the width of the diagonally extended gap of the U-shaped gap, and l1 is the length of the diagonally extended gap of the U-shaped gap. For circularly polarized feed, r a is the radius of the sector, sub_a is the side length of the 4×4 excess surface unit, sub_b is the distance between the 4×4 excess surface units, and f m is the distance between the center of the rectangular gap and the center of the SIW column, f x is the width of the rectangular gap, rr is the radius of the SIW column, and f y is the length of the rectangular gap, siw_w is the width of the SIW column, h3 is the thickness of the dielectric substrate, tapl_1 is the height of the trapezoidal groove of the SIW lower metal wall, tapl_2 is the length of the gap strip of the SIW lower metal wall, tapw_1 is the lower base length of the trapezoidal groove of the SIW lower metal wall, tapw_2 is the upper base length of the trapezoidal groove of the SIW lower metal wall, wg is the distance between the two gap strips of the SIW lower metal wall, and g is the width of the gap strip.

[0039] like Figure 9 (a) with Figure 9 As shown in (b), the transceiver unit 1 reflects LHCP in the range of 23.5 GHz to 29 GHz with a reflectivity of 20.9%; and transmits RHCP in the range of 24 GHz to 29 GHz with a transmittance of 18.9%.

[0040] like Figure 10 As shown in FIG, the circularly polarized feed has a peak gain of 8 dBi at a center frequency of 27 GHz and has a symmetrical and stable radiation pattern on the E-plane and H-plane.

[0041] like Figure 11 As shown in the figure, in the range of 22 GHz to 32 GHz, the circularly polarized feed has a 3dB axial ratio bandwidth of 37%.

[0042] like Figure 12 As shown in the figure, the broadband circularly polarized multi-beam transmission array antenna based on the SIW feeding network has a peak gain of 21.3dBi at the center frequency of 27GHz and a cross-polarization of less than -20dB.

[0043] like Figure 13 As shown, in the frequency range of 24.6GHz-28.4GHz, the antenna has a 3dB gain bandwidth of 14.3%, and in the frequency range of 24.8-30GHz, the antenna has an axial ratio bandwidth of 19%.

[0044] The specific implementation scheme described above further illustrates in detail the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above is only a specific implementation scheme of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes and modifications made by any technician in this field without departing from the concept and principle of the present invention should fall within the scope of protection of the present invention.

Claims

1. A broadband circularly polarized folded transmission array antenna based on a transceiver unit, characterized in that: The invention comprises a transceiver metasurface, a metal reflective surface (15) and a circularly polarized feed source which are sequentially stacked from top to bottom; the transceiver metasurface comprises a plurality of periodically arranged transceiver units (1); the transceiver unit (1) comprises an upper metal patch layer (2), an upper dielectric substrate layer (3), an intermediate metal grounding layer (4), an adhesive layer (5), a lower dielectric substrate layer (6), and a lower metal patch layer (7) which are sequentially stacked from top to bottom; a metal through hole (8) passes through from the upper metal patch layer (2) to the lower metal patch layer (7); the circularly polarized feed source comprises a 4×4 metasurface unit (9), an SIW upper dielectric substrate layer (10) which are sequentially stacked from top to bottom , SIW bonding layer (11), SIW upper metal wall (12), SIW lower dielectric substrate layer (13) and SIW lower metal wall (14); the transceiver unit (1) has polarization selection and polarization twisting performance, the left-handed circularly polarized electromagnetic wave output by the circularly polarized feed source can be reflected by the transceiver unit (1), the reflected left-handed circularly polarized wave is incident on the metal reflective surface (15) and twisted into a right-handed circularly polarized wave, and is incident on the lower metal patch layer (7) of several transceiver units (1) of the transceiver metasurface, and is transmitted to the upper metal patch layer (2) through the metal through hole (8) and twisted into a left-handed circularly polarized wave, and the height is reduced to one third of the focal length by folding the electromagnetic wave.

2. The broadband circularly polarized folded transmission array antenna based on a transceiver unit according to claim 1, characterized in that: The antenna controls 360-degree phase compensation by rotating the periodically arranged upper metal patch layer (2); the rotated metal patch is ahead of the non-rotated metal patch in phase, and 360-degree phase coverage is achieved while the transmission amplitude is not changed.

3. The broadband circularly polarized folded transmission array antenna based on a transceiver unit according to claim 2, characterized in that: The upper metal patch layer (2) is a circular patch with etched U-shaped gaps and diagonal rectangular gaps, and a split ring is added to the periphery of the circular patch to increase the working bandwidth.

4. The broadband circularly polarized folded transmission array antenna based on a transceiver unit according to claim 1, characterized in that: The metal reflective surface (15) is integrated on the SIW upper dielectric substrate layer (10) of the circularly polarized feed source.

5. The broadband circularly polarized folded transmission array antenna based on a transceiver unit according to claim 1, characterized in that: The 4×4 metasurface unit (9) of the circularly polarized feed is a square patch, and fan-shaped slots are cut at its diagonal to excite circularly polarized waves, thereby achieving a wider bandwidth; a long gap is etched in the center of the metal wall (12) on the SIW to achieve energy transmission.

6. The broadband circularly polarized folded transmission array antenna based on a transceiver unit according to claim 1, characterized in that: A pair of symmetrical slots are etched on the SIW lower metal wall (14) of the circularly polarized feed source to realize the conversion of the grounded coplanar waveguide (GCPW) to the SIW. The GCPW is connected to an external adapter and is fed to the 4×4 metasurface unit (9) after the GCPW to SIW conversion.

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