Wide-angular-domain polarization conversion metasurface with ultra-wideband characteristic and electronic equipment

Abstract

The invention discloses a wide-angle-domain polarization conversion metasurface with an ultra-wideband characteristic and electronic equipment, the wide-angle-domain polarization conversion metasurface with the ultra-wideband characteristic is formed by periodically arranging a plurality of polarization conversion metasurface units, each polarization conversion metasurface unit comprises two dielectric plate layers and three metal layers, the three metal layers are arranged to be a top-layer metasurface, a middle-layer metasurface and a bottom-layer metal floor from top to bottom, the two dielectric plate layers are arranged among the three metal layers at intervals, and two metal holes are formed in the longitudinal central axis of a metal strip of the top-layer metasurface. And each metal hole penetrates through the upper-layer dielectric plate and is in short circuit with the two rectangular metal patches in the middle of the middle-layer metasurface to form a magnetic resonator. Efficient cross polarization conversion can be achieved within the ultra-wideband range of 9.79-20.62 GHz, the polarization conversion rate is always kept to be 0.9 or above within the wide angular domain of 0-42 degrees, and the ultra-wideband high-polarization-conversion-efficiency ultra-wideband antenna has the advantages of being ultra-wideband, high in polarization conversion efficiency and stable in wide angular domain performance.

Description

Technical Field

[0001] The embodiments of the present invention relate to, but are not limited to, the field of electromagnetic metasurface technology, and in particular to a wide-angle polarization conversion metasurface and electronic device with ultra-wideband characteristics. Background Technology

[0002] Metasurfaces are novel artificial structures composed of subwavelength structural units arranged periodically or aperiodically in a plane, enabling precise multi-dimensional control of the phase, amplitude, and polarization state of electromagnetic waves. Applying metasurfaces to the control of electromagnetic wave polarization can effectively overcome the shortcomings of traditional polarizers, such as complex structures, narrow bandwidth, and high losses. Current research on polarization conversion metasurfaces mainly focuses on improving the operating bandwidth and polarization conversion efficiency of devices under perpendicular incidence, while research on achieving both stable polarization conversion performance and ultra-wideband characteristics in a wide-angle domain is relatively limited. Furthermore, existing polarization conversion metasurfaces suffer from poor polarization conversion stability and narrow bandwidth in the wide-angle domain. Therefore, developing wide-angle polarization conversion metasurfaces with ultra-wideband characteristics has become an urgent technical challenge. Summary of the Invention

[0003] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0004] This invention provides a wide-angle polarization conversion metasurface and electronic device with ultra-wideband characteristics, aiming to solve the technical problems of unstable polarization conversion performance and narrow polarization conversion bandwidth in wide-angle polarization conversion metasurfaces.

[0005] A first aspect of this invention provides a wide-angle polarization conversion metasurface with ultra-wideband characteristics, comprising a plurality of polarization conversion metasurface units arranged periodically. Each polarization conversion metasurface unit includes two dielectric substrate layers and three metal layers. The three metal layers are configured from top to bottom as a top metasurface, an intermediate metasurface, and a bottom metal ground plane. The two dielectric substrate layers are configured from top to bottom as an upper dielectric substrate layer and a lower dielectric substrate layer. The top metasurface is attached to the upper surface of the upper dielectric substrate layer, and the intermediate metasurface is attached to the lower surface of the upper dielectric substrate layer and the lower dielectric substrate. Between the upper surfaces of the layers, the bottom metal floor is attached to the lower surface of the lower dielectric layer; the top metasurface includes a metal strip located in the middle of the top metasurface and T-shaped metal patches located at both ends of the metal strip; the intermediate layer metasurface includes two rectangular metal patches and a bent-line metal patch extending laterally between the two rectangular metal patches; two metal holes are provided on the longitudinal central axis of the metal strip in the top metasurface, the two metal holes penetrate the upper dielectric layer and are short-circuited to the two rectangular metal patches to form a magnetic resonator.

[0006] In some embodiments, the two dielectric substrate layers are made of F4B board with a dielectric constant of 2.65 and a loss tangent of 0.0014.

[0007] In some embodiments, the arrangement period of the plurality of polarization conversion metasurface units p =5.3mm.

[0008] In some embodiments, the thickness of the upper dielectric layer h 1 = 1.7 mm, the thickness of the lower dielectric layer h 2 = 1mm.

[0009] In some embodiments, the T-shaped metal patch has a long side and a short side that are perpendicular to each other, the short side being in the same straight line direction as the two metal holes, and the length of the long side being... l 1 = 4.1 mm, the length of the metal strip l 2 = 3mm, the length of the shorter side l 3 = 0.71mm, the width of the longer side w 1 = 0.2 mm, the width of the metal strip w 2 = 1mm, the width of the shorter side w 3 = 0.1mm.

[0010] In some embodiments, the bent-line metal patch has multiple staggered square notches along its lateral extension direction, and the lateral extension length of the bent-line metal patch is... l 4 = 4.8mm, the length of the rectangular metal patch l 5 = 1.6mm, the side length of the square notch l 6 = 0.55mm, the full width of the bent-line metal patch w 4 = 0.9mm, the width of the rectangular metal patch w 5 = 0.8mm, the width of the square notch in the bent-line metal patch. w 6 = 0.35 mm.

[0011] In some embodiments, the spacing between the two metal holes d = 1.8mm, the radius of the metal hole r = 0.125mm.

[0012] In some embodiments, the metal layer is made of copper.

[0013] In some embodiments, the thickness of the metal layer t =0.035mm, conductivity is .

[0014] A second aspect of the present invention provides an electronic device including a wide-angle polarization conversion metasurface with ultra-wideband characteristics as described in the first aspect.

[0015] This invention provides a wide-angle polarization conversion metasurface and electronic device with ultra-wideband characteristics. The wide-angle polarization conversion metasurface is composed of multiple polarization conversion metasurface units arranged periodically. Each polarization conversion metasurface unit includes two dielectric substrate layers and three metal layers. The three metal layers are configured from top to bottom as a top metasurface, an intermediate metasurface, and a bottom metal ground plane. The two dielectric substrate layers are configured from top to bottom as an upper dielectric substrate and a lower dielectric substrate. The top metasurface is attached to the upper surface of the upper dielectric substrate, the intermediate metasurface is attached between the lower surface of the upper dielectric substrate and the upper surface of the lower dielectric substrate, and the bottom metal ground plane is attached... The top layer metasurface comprises a metal strip in the middle and T-shaped metal patches at both ends of the metal strip, which expands the polarization conversion bandwidth. The middle layer metasurface comprises two rectangular metal patches and a bent-line metal patch extending laterally between the two rectangular metal patches, which also expands the polarization conversion bandwidth. Two metal holes are provided on the longitudinal central axis of the metal strip in the top layer metasurface. The two metal holes penetrate the upper dielectric layer and are shorted to the two rectangular metal patches to form a magnetic resonator, thus realizing a polarization conversion metasurface with both ultra-wideband and wide-angle domain performance. Based on this, the wide-angle domain polarization conversion metasurface with ultra-wideband characteristics of this embodiment has an ultra-wide operating bandwidth and stable and efficient polarization conversion performance at wide incident angles.

[0016] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0017] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention, and do not constitute a limitation on the technical solutions of the present invention.

[0018] Figure 1 This is a schematic diagram of the unit structure of a wide-angle polarization conversion metasurface with ultra-wideband characteristics provided in an embodiment of the present invention, wherein (a) is a front view of the top layer metasurface, (b) is a front view of the middle layer metasurface, and (c) is a side view of the polarization conversion metasurface.

[0019] Figure 2This is a schematic diagram of the component decomposition of the electric field vector on the x-axis and y-axis in a device according to an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the reflection coefficient of a device according to an embodiment of the present invention when x and y polarized waves are incident perpendicularly.

[0021] Figure 4 This is a schematic diagram of the reflection phase of a device according to an embodiment of the present invention when x and y polarized waves are incident perpendicularly.

[0022] Figure 5 This is a schematic diagram of the reflection coefficient of a device according to an embodiment of the present invention when a v-polarized wave is incident perpendicularly.

[0023] Figure 6 This is a schematic diagram illustrating the changes in PCR at different incident angles using a device according to an embodiment of the present invention. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0025] It should be understood that in the description of the embodiments of the present invention, "multiple" (or "amounts") means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first," "second," etc., are used in the description, they are only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0026] To facilitate a more convenient description of the working principle of the embodiments of the present invention, the following introduction of relevant technical scenarios is given first.

[0027] Metasurfaces are novel artificial structures composed of subwavelength structural units arranged periodically or aperiodically in a plane, enabling precise multi-dimensional control of the phase, amplitude, and polarization state of electromagnetic waves. Applying metasurfaces to the control of electromagnetic wave polarization can effectively overcome the shortcomings of traditional polarizers, such as complex structures, narrow bandwidth, and high losses. Current research on polarization conversion metasurfaces mainly focuses on improving the operating bandwidth and polarization conversion efficiency of devices under perpendicular incidence, while research on achieving both stable polarization conversion performance and ultra-wideband characteristics in a wide-angle domain is relatively limited. Furthermore, existing polarization conversion metasurfaces suffer from poor polarization conversion stability and narrow bandwidth in the wide-angle domain. Therefore, developing wide-angle polarization conversion metasurfaces with ultra-wideband characteristics has become an urgent technical challenge.

[0028] To address the aforementioned technical problems, this invention provides a wide-angle polarization conversion metasurface and an electronic device with ultra-wideband characteristics. The wide-angle polarization conversion metasurface is composed of multiple polarization conversion metasurface units arranged periodically. Each polarization conversion metasurface unit includes two dielectric substrate layers and three metal layers. The three metal layers are configured from top to bottom as a top metasurface, an intermediate metasurface, and a bottom metal ground plane. The two dielectric substrate layers are configured from top to bottom as an upper dielectric substrate and a lower dielectric substrate. The top metasurface is attached to the upper surface of the upper dielectric substrate, the intermediate metasurface is attached between the lower surface of the upper dielectric substrate and the upper surface of the lower dielectric substrate, and the bottom metal ground plane... The ground plane is attached to the lower surface of the lower dielectric substrate layer. The top metasurface includes a metal strip in the middle and T-shaped metal patches at both ends of the metal strip. The introduction of the T-shaped metal patches expands the polarization conversion bandwidth. The middle layer metasurface includes two rectangular metal patches and a bent-line metal patch extending laterally between the two rectangular metal patches. The introduction of the bent-line metal patch also expands the polarization conversion bandwidth. Two metal holes are provided on the longitudinal central axis of the metal strip in the top metasurface. The two metal holes penetrate the upper dielectric substrate layer and are shorted to the two rectangular metal patches to form a magnetic resonator, realizing a polarization conversion metasurface with both ultra-wideband and wide-angle domain performance. Based on this, the wide-angle domain polarization conversion metasurface with ultra-wideband characteristics of this embodiment has an ultra-wide operating bandwidth and stable and efficient polarization conversion performance at wide incident angles.

[0029] like Figure 1 As shown, the present invention provides a wide-angle polarization conversion metasurface with ultra-wideband characteristics, which is composed of multiple polarization conversion metasurface units arranged periodically. Each polarization conversion metasurface unit includes two dielectric slab layers and three metal layers. The three metal layers are arranged from top to bottom as a top metasurface, an intermediate metasurface, and a bottom metal ground plane. The two dielectric slab layers are spaced apart between the three metal layers. The top metasurface is attached to the upper surface of the upper dielectric slab layer, the intermediate metasurface is attached between the lower surface of the upper dielectric slab layer and the upper surface of the lower dielectric slab layer, and the bottom metal ground plane is attached to the lower surface of the lower dielectric slab layer.

[0030] Understandably, the top metasurface consists of a metal strip in the middle and T-shaped metal patches at both ends of the metal strip, with the introduction of the T-shaped metal patches extending the polarization conversion bandwidth.

[0031] Understandably, the intermediate metasurface comprises two rectangular metal patches and a laterally extending metal bend line located between the two rectangular patches. The introduction of the metal bend line also expands the polarization conversion bandwidth.

[0032] Understandably, two metal holes are located in the longitudinal direction of the central metal strip in the top metasurface. In this example, the two metal holes are located on the longitudinal central axis of the metal strip, penetrate the upper dielectric layer, and are shorted to two rectangular patches on the intermediate metasurface to form a magnetic resonator, achieving stable polarization conversion performance in the ultra-wideband and wide-angle domains.

[0033] It is understandable that the material of the two dielectric substrate layers is F4B board with a dielectric constant of 2.65 and a loss tangent of 0.0014.

[0034] It is understandable that the arrangement period of multiple polarization conversion metasurface units... p =5.3mm.

[0035] It is understandable that the thickness of the upper dielectric layer in the dielectric substrate layer... h 1 = 1.7 mm, the thickness of the lower dielectric layer h 2 = 1mm.

[0036] It is understandable that the T-shaped metal patch has mutually perpendicular long and short sides, with the short side aligned with the two metal holes in a straight line, and the length of the long side... l 1 = 4.1mm, the length of the metal strip l 2 = 3mm, the length of the shorter side l 3 = 0.71mm, the width of the longer side w 1 = 0.2mm, the width of the metal strip w 2 = 1mm, the width of the shorter side w 3 = 0.1mm.

[0037] It is understandable that the bent-line metal patch has multiple staggered square notches along its lateral extension direction, and the lateral extension length of the bent-line metal patch... l 4 = 4.8mm, the length of the rectangular metal patch l 5 = 1.6mm, the side length of the square notch l 6 = 0.55mm, the full width of the bent-line metal patch. w 4 = 0.9mm, the width of the rectangular metal patch w 5 = 0.8mm, the width of the square notch in the bent-line metal patch. w 6 = 0.35mm.

[0038] Understandably, the metal layer can be made of materials such as gold, silver, or copper, but copper is often chosen in practical applications. The thickness of the metal layer... t =0.035mm, conductivity is .

[0039] Miniaturization of the device is achieved by using a magnetic resonator structure formed by loading metal holes, thereby reducing the sensitivity of polarization conversion performance to the incident angle and significantly improving the stability of the device performance over a wide angle range. By loading a T-shaped metal patch on the top layer and a bent line in the middle layer, more resonant frequencies can be introduced, thus greatly expanding the polarization conversion bandwidth of the device. The bottom metal layer can totally reflect the incident wave.

[0040] Furthermore, the present invention also proposes a specific embodiment, which uses software simulation calculations, such as... Figures 2 to 6 As shown, in the simulation, the dielectric constant of the two dielectric layers is set to 2.65, and the loss tangent is 0.0014; the three metal layers are all copper foil with a conductivity of The geometric parameters of the metasurface unit structure are: l1 = 4.1 mm, l2 = 3 mm, l3 = 0.71 mm, l4 = 4.8 mm, l5 = 1.6 mm, l6 = 0.55 mm, w1 = 0.2 mm, w2 = 1 mm, w3 = 0.1 mm, w4 = 0.9 mm, w5 = 0.8 mm, w6 = 0.35 mm.

[0041] To better understand the electromagnetic response of the polarization converter, this embodiment uses a v-polarized wave incident on a metasurface as an example for analysis. The electric field vector of the v-polarized wave can be decomposed into two orthogonal components along the x-axis and y-axis, such as... Figure 2 As shown.

[0042] The electric field of the incident wave is represented as:

[0043] , in and Let x and y represent the electric field components of the incident electric field along the x and y directions, respectively. Indicates phase.

[0044] The electric field of the reflected wave is represented as: , in and Let represent the reflection coefficients of the incident electric field in the x and y directions, respectively. Due to the anisotropy of the metasurface, therefore... and There is a phase difference .when , When the polarization direction of the reflected wave's electric field is deflected by 90°, the polarization direction of the reflected wave's electric field will be deflected by 90°. To study the device's performance, the amplitude and phase of the reflection coefficient of the polarization-conversion metasurface unit under perpendicular incident x and y polarized waves were simulated using CST simulation software. The results are as follows: Figure 3, Figure 4 As shown. Figure 3 The results show that the polarization-conversion metasurface operates within the frequency range of 9.79–20.62 GHz. On the other hand, from Figure 4 It can be observed that the phase difference between the two orthogonal components fluctuates around 180° within the same frequency range. Therefore, this metasurface unit can achieve cross-polarization conversion in the frequency range of 9.79–20.62 GHz.

[0045] For reflective cross-polarization converters, polarization conversion efficiency (PCR) is an important indicator of their performance, and can be expressed as follows: , in, and Representing the cross-polarization reflection coefficient and the co-polarization reflection coefficient respectively, when At this point, the polarization conversion rate is 1, and the polarization conversion effect reaches its optimal level. Full-wave simulation of the polarization-converting metasurface unit under perpendicular incidence of a v-polarized wave was performed using the commercial software CST, and the reflection coefficient was obtained as follows: Figure 5 As shown in the figure. Simulation results show that the polarization-converting metasurface generates five resonant frequencies—10.71, 11.56, 13.62, 15.52, and 19.67 GHz—under perpendicular incidence of a v-polarized wave. This multi-resonance characteristic greatly extends the polarization conversion bandwidth. From the above expression for the polarization conversion rate, it can be concluded that the polarization conversion rate of this polarization-converting metasurface exceeds 0.9 in the frequency range of 9.79–20.62 GHz, with a relative bandwidth of 71.23%. Furthermore, as… Figure 6 As shown, when the angle of incidence At that time, the polarization conversion efficiency still exceeded 0.9 in the 9.73-20.97 GHz range, and the bandwidth change was only 3.8%, demonstrating good wide-angle stability.

[0046] In summary, the wide-angle polarization conversion metasurface with ultra-wideband characteristics proposed in this invention possesses an ultra-wide operating bandwidth and exhibits stable and efficient polarization conversion performance at wide incident angles. Accordingly, this invention has at least the following advantages: It features an ultra-wide operating bandwidth and high-efficiency polarization conversion performance.

[0047] It can achieve efficient polarization conversion within the range of 0-42°, and the bandwidth is stable.

[0048] Based on this, the wide-angle polarization conversion metasurface with ultra-wideband characteristics of the present invention can achieve efficient cross-polarization conversion in the ultra-wideband range of 9.79-20.62GHz, and the polarization conversion rate is always maintained above 0.9 in the wide-angle range of 0-42°, thus possessing the characteristics of ultra-wideband, high polarization conversion efficiency and stable performance in the wide-angle range.

[0049] In addition, an embodiment of the present invention also discloses an electronic device. Since the electronic device adopts the wide-angle polarization conversion metasurface with ultra-wideband characteristics described above, the electronic device can achieve the same technical effect as the wide-angle polarization conversion metasurface with ultra-wideband characteristics described above, which will not be described in detail here.

[0050] The above provides a detailed description of the preferred embodiments of the present invention. However, the present invention is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention. All such equivalent modifications or substitutions are included within the scope defined by the claims of the present invention.

Claims

1. A wide-angle polarization conversion metasurface with ultra-wideband characteristics, characterized in that, The application relates to a wide-angle polarization conversion metasurface with super wideband characteristics, which is composed of a plurality of polarization conversion metasurface units arranged periodically, each of the polarization conversion metasurface units comprises two dielectric plate layers and three metal layers, the three metal layers are arranged from top to bottom as a top layer metasurface, an intermediate layer metasurface and a bottom layer metal ground plate, the two dielectric plate layers are arranged from top to bottom as an upper dielectric plate layer and a lower dielectric plate layer, the top layer metasurface is attached to the upper surface of the upper dielectric plate layer, the intermediate layer metasurface is attached between the lower surface of the upper dielectric plate layer and the upper surface of the lower dielectric plate layer, and the bottom layer metal ground plate is attached to the lower surface of the lower dielectric plate layer; the top layer metasurface comprises a metal strip located in the middle of the top layer metasurface and T-shaped metal patches located at both ends of the metal strip; the intermediate layer metasurface comprises two rectangular metal patches and a bending line metal patch extending transversely between the gaps of the two rectangular metal patches; two metal holes are arranged on the longitudinal central axis of the metal strip of the top layer metasurface, the two metal holes penetrate the upper dielectric plate layer and are short-circuited with the two rectangular metal patches to form a magnetic resonator.

2. The wide-angle polarization conversion metasurface with ultra-wideband characteristics according to claim 1, characterized in that, The material of the two dielectric plate layers is F4B plate with a dielectric constant of 2.65 and a loss tangent of 0.0014.

3. The wide-angle polarization conversion metasurface with ultra-wideband characteristics of claim 1, wherein, An arrangement period of a plurality of the polarization conversion metasurface units p = 5.3 mm.

4. The wide-angle polarization conversion metasurface with ultra-wideband characteristics of claim 1, wherein, thickness of the upper media sheet layer h 1 = 1.7 mm, thickness of the lower media sheet layer h 2 = 1 mm.

5. The wide-angle polarization conversion metasurface with ultra-wideband characteristics of claim 1, wherein, The T-shaped metal patch has mutually perpendicular long side and short side, the short side is in the same straight line direction with two metal holes, the length of the long side l 1= 4.1mm, the length of the metal strip l 2= 3mm, the length of the short side l 3= 0.71mm, the width of the long side w 1= 0.2mm, the width of the metal strip w 2= 1mm, the width of the short side w 3= 0.1mm.

6. The wide-angle polarization conversion metasurface with ultra-wideband characteristics of claim 1, wherein, The bent-line metal patch is provided with a plurality of square notches arranged in staggered manner along the direction of transverse extension, the length of the bent-line metal patch in the direction of transverse extension l 4= 4.8mm, the length of the rectangular metal patch l 5= 1.6mm, the side length of the square notch l 6=0.55mm, the full width of the bent-line metal patch w 4= 0.9mm, the width of the rectangular metal patch w 5= 0.8mm, the width of the bent-line metal patch at the position where the square notch is formed w 6= 0.35mm.

7. The wide-angle polarization conversion metasurface with ultra-wideband characteristics of claim 1, wherein, The distance between two said metal holes d = 1.8mm, the radius of said metal hole r = 0.125mm.

8. The wide-angle polarization conversion metasurface with ultra-wideband characteristics of claim 1, wherein, The material of the metal layer is copper.

9. The wide-angle polarization conversion metasurface with ultra-wideband characteristics of claim 1, wherein, The thickness of the metal layer t = 0.035 mm, the conductivity is 0.035 mm, the conductivity is 10. An electronic device, comprising: The application further discloses a wide-angle polarization conversion metasurface with super wideband characteristics, which comprises the wide-angle polarization conversion metasurface as claimed in any one of claims 1 to 9.

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