Dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna and communication equipment

Abstract

The present invention discloses a dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna and communication equipment, including a feed source and a radiation structure realizing reflection / transmission function, wherein the feed source is arranged above the radiation structure, wherein the radiation structure includes N×M radiation units arranged in an array, wherein the radiation unit includes two layers of dielectric substrates arranged in affixed manner, wherein the top layer, the middle layer and the bottom layer of the two layers of dielectric substrates are respectively provided with metal patches of the same structure, wherein the metal patches are provided with orthogonal X-axis branches and Y-axis branches, wherein the Y-axis branches in the three layers of metal patches are completely consistent in size, the X-axis branches in the top layer and the middle layer are completely consistent in size, and the X-axis branches in the bottom layer are different in size from the X-axis branches in the top layer and the middle layer. The planar transmission and reflection metasurface antenna provided by the present invention has the characteristics of planarization, flexible design, dual polarization, multi-beam, high aperture efficiency and focusing efficiency.

Description

Technical Field

[0001] The present invention relates to the field of communications, and in particular to a dual-frequency dual-polarization multifunctional transmission and reflection type metasurface antenna and communication equipment. Background Art

[0002] High-gain and multi-beam antennas have attracted the attention of researchers due to their practical value in communication applications and radar systems. In recent years, many high-gain and multi-beam antennas based on metasurfaces have emerged. At the same time, focusing antennas also play an important role in point-to-point and point-to-multipoint applications such as near-field communications and wireless energy transmission, and various types of focusing antennas are developing rapidly. Metasurfaces have attracted widespread attention because they introduce phase mutations during the propagation of electromagnetic waves to replace the phase difference introduced by the feed in traditional devices, and have the advantages of small size, low loss, simple production, and flexible control of wavefronts. They have been widely used in focusing, abnormal refraction / reflection, RCS reduction, multi-frequency and multi-function antennas, etc.

[0003] At present, most metasurface antennas can only realize one of the transmission or reflection modes, and the utilization of polarization is not high. The operating frequency is single, and most units are insensitive to polarization, and thus can only realize a single function. There are very few metasurfaces that can work in transmission and reflection modes, and the structures that have appeared are relatively complex, using four or more metal layers to achieve 360° phase coverage. At present, there are not many antennas that work in transmission and reflection modes, and there are many dielectric layers. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna and communication equipment, which can realize different functions in the transmission and reflection modes respectively, and can realize reflection of single-beam or multi-beam antenna under the irradiation of one polarization incident wave, and realize transmission focusing when another polarization incident wave is incident.

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

[0006] A dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna, comprising a feed source and a radiation structure realizing reflection / transmission functions, wherein the feed source is arranged above the radiation structure, the radiation structure comprises N×M radiation units arranged in an array, the radiation unit comprises two layers of dielectric substrates bonded together, the top layer, the middle layer and the bottom layer of the two dielectric substrates are respectively provided with metal patches of the same structure, the metal patches are provided with orthogonal X-axis branches and Y-axis branches, the Y-axis branches in the three layers of metal patches are completely consistent in size, the X-axis branches in the top layer and the middle layer are completely consistent in size, and the X-axis branches in the bottom layer are different in size from those in the top layer and the middle layer.

[0007] Furthermore, the X-axis branches include X-axis positive branches and X-axis reverse branches with the same structure, both of which are composed of X-axis head branches, X-axis middle branches and X-axis terminal branches vertically connected in sequence, and the length and width of the X-axis terminal branch of the bottom metal patch are fixed values.

[0008] Furthermore, the sizes of the X-axis head end branches and the X-axis middle branches of the three-layer metal patch are the same, and the size of the X-axis end branches of the bottom layer metal patch is larger than the X-axis end branches of the top layer metal patch and the middle layer metal patch.

[0009] Furthermore, the Y-axis branches include Y-axis positive branches and Y-axis reverse branches with the same structure, both of which are composed of a Y-axis head branch, a Y-axis middle branch and a Y-axis terminal branch that are vertically connected in sequence.

[0010] Furthermore, the X-axis branches and the Y-axis branches are symmetrical about the center point of the dielectric substrate.

[0011] Furthermore, when the incident wave is polarized in the X direction, it corresponds to the reflection mode, and the reflection phase is regulated by adjusting the X-axis branches of the top layer and the middle layer; when the incident wave is polarized in the Y direction, it corresponds to the transmission mode, and the transmission phase is regulated by adjusting the Y-axis branches of the three-layer metal patch.

[0012] Furthermore, when working in the reflection mode, the frequency is 16 GHz and the X-axis head-end branch varies between 1.5 and 6 mm.

[0013] Furthermore, when working in transmission mode, the frequency is 13 GHz and the middle branch of the Y axis varies between 0.4 and 6.2 mm.

[0014] Furthermore, the array shape is circular or square.

[0015] A communication device comprises the dual-frequency dual-polarization multifunctional transmission and reflection type metasurface antenna.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] (1) The dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna design is flexible in design. In one design, it can work in reflection or transmission mode under different polarization incident waves. As a verification, the present invention provides an embodiment of realizing reflection multi-beam or single-beam high-gain antenna under different polarization incident waves, and realizing different numbers and positions of focus points through transmission;

[0018] (2) The dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna is formed by bonding three layers of metal and two layers of dielectrics. It has a wide phase shift range and a high reflection and transmission amplitude, which reduces the processing difficulty and cost.

[0019] (3) The radiation unit of the present invention adopts a three-layer metal structure, wherein the upper and middle layers of the metal patch structure are consistent, and the bottom metal patch structure is partially different from the upper and middle layers, so that the phases of the transmission and reflection waves can be adjusted respectively. The required different compensation phases can be adjusted simply by adjusting the length of the branches. The mutual interference between the branches adjusting the phase in the unit is small, and the reflection and transmission modes operate at different frequencies;

[0020] (4) The metasurface antenna has a planar structure, is easy to process and assemble, and has the advantage of high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic diagram of the three-dimensional structure of Example 1 of the present invention;

[0022] 2(a), 2(b) and 2(c) are respectively a side view of the radiation unit of Embodiment 1 of the present invention, a top layer and middle layer metal patch structure diagram and a bottom layer metal patch structure schematic diagram.

[0023] Figure 3 is a top view of the planar array of Example 1 of the present invention;

[0024] Figure 4 is a phase shift curve diagram of the branch length Lx in the x direction under the reflection mode of the radiation unit of Example 1 of the present invention;

[0025] Figure 5 is a phase shift curve diagram of the branch length Ly in the y direction in the transmission mode of the radiation unit of Example 1 of the present invention;

[0026] Figure 6 is a phase distribution diagram corresponding to the four-beam antenna designed in the reflection mode in Example 1 of the present invention;

[0027] Figure 7 is a phase distribution diagram obtained when the focal length of the vertical coordinate origin is 50 mm in the transmission mode of Example 1 of the present invention;

[0028] Figure 8 Embodiment 1 of the present invention Figure 5 In this case, the four-beam three-dimensional pattern is formed by the x-polarized incident wave illumination;

[0029] Fig. 9 Embodiment 1 of the present invention Figure 6 The yoz plane focusing effect diagram formed by the y-polarized incident wave illumination in the case of

[0030] Fig.10 is a phase distribution diagram corresponding to the single-beam high-gain antenna designed in the reflection mode in Example 2 of the present invention;

[0031] Fig.11 is a phase distribution diagram of two focal points at different positions formed in the transmission mode according to the second embodiment of the present invention;

[0032] Fig.12 Embodiment 2 of the present invention Fig. 9 The three-dimensional directivity diagram of a single beam formed by the x-polarized incident wave in the case of

[0033] Fig.13 Embodiment 2 of the present invention Fig.10 The yoz plane focusing effect diagram formed by the y-polarized incident wave irradiation under the condition; DETAILED DESCRIPTION

[0034] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0035] Example 1

[0036] In this embodiment, the X-axis is the vertical direction, and the Y-axis is the horizontal direction.

[0037] like Figure 1 , Figure 2(a), Figure 2(b), Figure 2(c) and Figure 3 As shown, a dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna includes a feed source 1 and a radiation structure that realizes reflection / transmission functions. The radiation structure is a metasurface structure, including N×M radiation units 3 arranged in an array. The radiation unit includes two layers of dielectric substrates 2 that are bonded together, one layer is a double-sided metal structure, and the other layer is a single-sided metal structure; its three layers of metal structures are respectively arranged at the top layer, middle layer and bottom layer of the bonded dielectric substrate, and the metal structure is a metal patch. Among them, the relevant parameters of the unit in Figure 2 are optimal when: P = 9mm, h = 2mm, w = 0.4mm, w1 = 0.8mm, L1 = 1.5mm, L2 = 2.45mm, L3 = 4.7mm.

[0038] In this embodiment, the feed source 1 irradiates the metasurface at a height of 60 mm from the planar reflective array. Figure 3 As shown, in this embodiment, the material of the dielectric substrate 2 is a dielectric plate with a dielectric constant of 2.55, the length and width of the array are both 11.7 cm, and the total height of the two layers of dielectric plates is 4 mm.

[0039] The feed source generates a linearly polarized wave to illuminate the metasurface; the branch size of each radiation unit of the metasurface is adjustable to generate the phase shift compensation required at the position, and at the same time, the unit structure is sensitive to the polarization of the incident wave, and can enable transmission or reflection of incident waves with different polarizations. The transmission or reflection phase is regulated by adjusting the branch sizes in two orthogonal directions, and the transmission and reflection mode operating frequencies corresponding to the two polarizations are different.

[0040] Furthermore, the structures of the three-layer metal patches are the same, including orthogonal X-axis branches and Y-axis branches. The sizes of the branches in the Y-axis direction in the three-layer metal patches are completely consistent, the sizes of the X-axis branches in the top and middle layers are completely consistent, and the sizes of the X-axis branches in the bottom layer are different from those in the top and middle layers.

[0041] Specifically, the X-axis branches include X-axis positive branches and X-axis negative branches with the same structure, which are symmetrical about the origin of the coordinate axis and are composed of X-axis head branches, X-axis middle branches and X-axis terminal branches connected vertically in sequence, forming a door-shaped structure, and the openings of the X-axis positive branches and X-axis negative branches are all facing the Y axis. The sizes of the X-axis branches of the top and middle layers are exactly the same. The head branch L1 and the middle branch L2 of the X-axis branches of the bottom layer are the same as those of the top and middle layers. Only the X-axis terminal branch L3 of the X-axis branches of the bottom layer is longer and wider than the first two layers, and is fixed and unchanged, acting as a reflector.

[0042] The Y-axis branches include Y-axis positive branches and Y-axis reverse branches with the same structure, which are symmetrical about the origin of the coordinate axis and are composed of Y-axis head branch, Y-axis middle branch and Y-axis end branch Ly connected vertically in sequence. The three branches form a door-like shape with openings facing the X-axis. The Y-axis head branch and the Y-axis middle branch are fixed.

[0043] The feed source may be a microstrip antenna or a horn antenna with low side lobes and low back lobes, or other antenna types that generate linearly polarized waves.

[0044] The radiation structure is sensitive to the polarization of the incident wave, and can transmit or reflect incident waves of different polarizations. The transmission or reflection phase can be controlled by adjusting the branch sizes in two orthogonal directions to achieve the required function.

[0045] Further, if Figure 4 and Figure 5 As shown, when the incident wave is polarized in the x-direction, it corresponds to the reflection mode. At this time, the branches in the x-axis direction of the top layer and the middle two layers are strongly coupled, and the partial reflector of the bottom layer reflects the electromagnetic wave. The reflection phase can be controlled by adjusting the X-axis end branch Lx of the upper, middle and lower layers of metal in the x-direction. When the incident wave is polarized in the y-direction, it corresponds to the transmission mode. At this time, the branches in the x-axis direction of the upper, middle and lower layers are strongly coupled. Since there is no reflective metal plate, the incident wave is coupled in the three layers of metal and transmitted. The transmission phase can be controlled by adjusting the Y-axis end branch Ly of the upper, middle and lower layers of metal. The operating frequency of the reflection mode is 16GHz, and the operating frequency of the transmission mode is 13GHz. See. Figure 4 In the reflection mode, the x-axis end branch Lx varies between 1.5 and 6 mm, and the corresponding reflection amplitude and phase shift range curve. Figure 5In the transmission mode, the Y-axis end branch Ly in the y direction varies between 0.4 and 6.2 mm, and the corresponding phase shift range curves of different frequencies meet the design requirements of the radiation unit.

[0046] The radiation unit includes a three-layer metal structure, which can respectively realize reflection and transmission for incident waves of different polarizations. In the reflection mode, a reflection phase shift control of 360° can be achieved, and in the transmission mode, a transmission phase shift control of 340° can be achieved.

[0047] The radiation units are periodically arranged on the dielectric substrate to form an array structure, and the array can be a circular, rectangular or other structure.

[0048] The required modulation phase of the radiation unit is related to the position of the radiation unit on the upper surface of the dielectric substrate, and different phase compensations are calculated according to different functional requirements.

[0049] The operating frequencies of the metasurface in the transmission mode and the reflection mode are different. The required compensation phase is calculated according to different requirements so that the required phase at the position is generated on the operating frequency.

[0050] The planar transmission metasurface antenna of the present invention takes the center of the array as the coordinate origin, and the principle of generating multiple beams can be explained by the formula: Where m is the number of beams, is the direction of the mth beam, is the location of the unit, H i,j is the distance between the speaker phase center and the different unit positions. The principle of focusing is similar and can be explained by the formula: Where Φ(m,n) represents the distance phase difference between the radiation unit located at (mp,np) and the origin of the coordinate system to the focus F, and the total phase difference to be compensated can be expressed as Φ t o tal (m,n)=Φ h o rn (m,n)+Φ(m,n),Φ horn (m,n) represents the distance phase difference between each radiating unit on the metasurface and the origin of the coordinates to the phase center of the feed source. The two are superimposed to form the total compensation phase Φ total (m,n), for forming multiple focuses, the total compensation phase is obtained by vector superposition of the phase required to be compensated for each single focus.

[0051] In this embodiment, the antenna is a four-beam antenna in the reflection mode, and the four beam directions are respectively and The transmission mode is focused, and the focal distance from the surface coordinate origin is set to 50mm. Figure 6 and Figure 7The phase distribution of the two modes in the planar array is shown in the figure. Each radiating element occupies an area of ​​9 mm in length and width, forming a 13×13 array. The length of each branch of the radiating element is determined according to the phase required for the position of the dielectric substrate where it is located. The gain of the feed used in the embodiment at 13 GHz and 16 GHz is 10.6 dB and 12.2 dB respectively.

[0052] See also Figure 8 and Fig. 9 , respectively, are different results obtained in this embodiment under the irradiation of polarized incident waves in the x direction and the y direction, Figure 8 It is a four-beam antenna in reflection mode. The maximum gain of the four beams is 16.4dB, and the side lobes are all lower than -14dB. Fig. 9 This is the near-field focusing diagram formed in the transmission mode. From the focused electric field intensity diagram, it can be observed that the focusing effect of the metasurface is good. The electromagnetic wave is focused to form a focal spot. Its -3dB focal width and focal depth are 12mm and 38mm respectively. The corresponding side lobes at the focal plane are all lower than -10dB.

[0053] This antenna is designed to achieve high-gain antenna with high aperture efficiency or multi-beam antenna with any number and direction in reflection mode. At the same time, any number and any position of focusing points can be designed in transmission mode.

[0054] Embodiment 2:

[0055] The antenna structure, dielectric material, etc. of the present invention are the same as those of Example 1, except that it is a single-beam high-gain antenna in the reflection mode, and two focusing points at different positions are realized in the transmission mode, and the phases required to be compensated by the radiation units are different.

[0056] The principle of generating multiple focal points can be explained by the formula: Where n is the number of foci, K n(i , j ) is the distance from the nth focus to the (i,j)th unit on the hypersurface, H i,j is the distance between the speaker phase center and different unit positions.

[0057] See also Fig.10 , which is the phase distribution when the single beam position is (θ=30°,φ=90°), Fig.11 The phase distribution diagram when the two focusing points are (0, -40, 50mm) and (0, 40, 50mm). Fig.12 and Fig.13 , which are different results obtained in this embodiment under the irradiation of polarized incident waves in the x-direction and the y-direction. Fig.11The single-beam high-gain antenna obtained under simulation has a maximum gain of 22.8dB, a half-power beamwidth of approximately 10.5°, a -1dB gain bandwidth of 15.7-16.6GHz, a directivity coefficient of 23dB, and an aperture efficiency of 53%. Fig.12 This is the near-field focusing diagram formed in the transmission mode. It can be seen that the two focusing points are clearly visible and the focusing effect is good.

[0058] Example 3

[0059] A communication device comprises a dual-frequency dual-polarization multifunctional transmission and reflection type metasurface antenna as described in Example 1.

[0060] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna, characterized in that: It includes a feed source and a radiation structure that realizes reflection / transmission functions, wherein the feed source is arranged above the radiation structure, the radiation structure includes N×M radiation units arranged in an array, the radiation unit includes two layers of dielectric substrates that are bonded together, the top layer, the middle layer and the bottom layer of the two dielectric substrates are respectively provided with metal patches of the same structure, the metal patches are provided with orthogonal X-axis branches and Y-axis branches, the sizes of the Y-axis branches in the three layers of metal patches are completely consistent, the sizes of the X-axis branches in the top layer and the middle layer are completely consistent, and the sizes of the X-axis branches in the bottom layer are different from those of the X-axis branches in the top layer and the middle layer; The X-axis branches include X-axis positive branches and X-axis reverse branches with the same structure, both of which are composed of X-axis head branches, X-axis middle branches and X-axis terminal branches connected vertically in sequence, and the length and width of the X-axis terminal branch of the bottom metal patch are fixed values; The sizes of the X-axis head end branches and the X-axis middle branches of the three-layer metal patch are the same, and the size of the X-axis end branches of the bottom metal patch is larger than the X-axis end branches of the top metal patch and the middle metal patch; The Y-axis branches include a Y-axis positive branch and a Y-axis reverse branch with the same structure, each of which is composed of a Y-axis head branch, a Y-axis middle branch and a Y-axis terminal branch connected vertically in sequence; The X-axis branches and the Y-axis branches are symmetrical about the center point of the dielectric substrate.

2. The dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna according to claim 1, characterized in that: When the incident wave is polarized in the X direction, it corresponds to the reflection mode, and the reflection phase is regulated by adjusting the X-axis branches of the top and middle layers; when the incident wave is polarized in the Y direction, it corresponds to the transmission mode, and the transmission phase is regulated by adjusting the Y-axis branches of the three-layer metal patch.

3. The dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna according to claim 2, characterized in that: When working in reflection mode, the frequency is 16GHz and the X-axis head end branch varies between 1.5 and 6mm.

4. The dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna according to claim 2, characterized in that: When working in transmission mode, the frequency is 13GHz and the middle branch of the Y axis varies between 0.4 and 6.2mm.

5. The dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna according to claim 1, characterized in that: The array shape is circular or square.

6. A communication device, comprising the dual-frequency dual-polarization multifunctional transmission and reflection metasurface antenna as described in any one of claims 1 to 5.

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