CN113991297B - Wide-angle beam scanning antenna array based on super-surface and artificial surface plasmon - Google Patents

Abstract

A wide-angle beam scanning antenna array based on a super surface and artificial surface plasmons comprises a micro-strip artificial surface plasmon antenna array and a super surface. The microstrip artificial surface plasmon antenna array comprises three microstrip artificial surface plasmon antenna units. The microstrip artificial surface plasmon antenna unit comprises a microstrip structure feed part, a microstrip radiation part with holes on an upper layer metal wire and a series of metal vias. The super surface comprises a plurality of rectangular metal rings and circular metal patches. According to the beam scanning antenna array, the hole structure is formed in the upper metal layer of the microstrip line, so that quasi-TEM waves are successfully converted into TM waves, and the high-order mode characteristics of the quasi-TEM waves are utilized, so that the performance of wide-angle beam scanning is realized; the high-gain performance is realized by forming the array structure; the beam scanning angle of the antenna array is further widened by placing the super-surface structure on the array antenna; compared with the traditional beam scanning antenna, the antenna has higher gain and beam scanning angle.

Description

Wide-angle beam scanning antenna array based on metasurface and artificial surface plasmon

technical field

The invention relates to beam scanning antennas, in particular to a wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons.

Background technique

In recent years, with the rapid development of wireless communication technology, wide-angle beam scanning antennas play an increasingly important role in communication systems. Artificial surface plasmon polaritons (Spoof surface plasmon polarons, SSPPs) are electromagnetic waves generated by the coupling of free electrons and light in metals, which inherit most of the excellent properties of surface plasmon polaritons (SPPs), such as field confinement and non-diffraction limit, etc. With the development of scientific research, various SSPPs have been proposed and applied in practice.

SSPPs waves are slow wave modes that do not radiate energy into free space. In order to radiate this slow wave into free space, the tapered structure designed by Yin et al. "Direct radiations of surface plasmonpolariton waves by gradient groove depth and flaring metal structure" was published in IEEEAntennas Wireless Propag.Lett.(2016,15:865– 868) published on; the load resonant unit structure designed by Yin et al. "Frequency-controlled broad-angle beam scanning of patch array fed by spoof surface plasmon polaritons" in IEEE Trans.Antennas Propag.(2016,64(12):5181–5189 .) published on; Periodic leaky wave antenna designed by Zheng et al. "High-gain and widebandantenna arrays: Introducing three patch antenna arrays to show the advantages of SPPWs used in a feed network" in IEEE Antennas Propag.Mag.(2016,58 (40):22–34). Recently, Wang et al. proposed a new SSPPs design in "Anultra-thin coplanar waveguide filter based on the spoof surface plasmon polaritons" published in Appl.Phys.Lett., (2018,113(7):071101), It uses the periodic hole array etched on the metal line to realize the conversion of quasi-TEM mode to TM mode, and achieves high efficiency, multi-band performance, etc., while removing the traditional mode conversion structure to achieve miniaturization characteristics. This design concept may well radiate SSPPs wave excitation into free space.

At present, most of the beam-scanning antennas are based on the proposed flared coplanar waveguide to excite and use the gradual gear-like structure as the feed structure, and realize the beam-scanning characteristics by exciting structures such as circular metal patches. However, these designs are not conducive to the improvement of beam scanning angle and bandwidth. Therefore, Wang et al. proposed a method based on coplanarity in the document IEEE Trans. The beam scanning antenna of the waveguide, although this structure realizes the wide-angle beam scanning angle, it is not conducive to forming an array. Nowadays, with the rapid development of microwave technology, the requirements for the bandwidth, beam scanning angle, and antenna gain of the beam scanning antenna are also continuously improved. Therefore, how to design a beam scanning antenna that satisfies the characteristics of wide bandwidth, wide beam scanning angle, and high gain has become a research hotspot and difficulty.

Contents of the invention

The object of the present invention is to provide a wide-bandwidth, wide-beam scanning angle, high-gain metasurface and artificial surface plasmon wide-angle beam scanning antenna array.

For realizing the above-mentioned purpose of the invention, the technical scheme of the present invention is as follows:

A wide-angle beam scanning antenna array based on metasurface and artificial surface plasmon polarons (Spoof surface plasmon polarons, SSPPs), including two parts: an artificial surface plasmon antenna array with a microstrip structure and a metasurface. The microstrip artificial surface plasmon antenna array consists of three microstrip artificial surface plasmon antenna elements. The microstrip artificial surface plasmon antenna unit is composed of a microstrip structure feeding part, a microstrip radiation part with holes in the upper metal line, and a series of metal through holes. The artificial surface plasmon antenna array with microstrip structure is printed on a dielectric substrate with a thickness of 2.286 mm. The metasurface consists of several rectangular metal rings and circular metal patches arranged in a periodic structure, which are printed on the front and back sides of a three-layer dielectric substrate with a thickness of 0.254 mm.

As a further improved technical solution of the present invention, each array element in the artificial surface plasmon antenna array is fed by an SMA connector. The upper metal wire of the antenna unit is connected to the inner core of the SMA structure, and the lower metal ground is connected to the outer core of the SMA structure.

As a further improved technical solution of the present invention, the widths of the upper metal line with holes and the lower metal ground of the antenna unit in the artificial surface plasmon antenna array of microstrip structure are 9mm and 20mm respectively, and the width of the hole in the upper metal line is 9mm and 20mm respectively. The radius is 4.3 mm, the radius of the metal through holes is 0.2 mm, and the distance between the metal through holes is 0.6 mm.

As a further improved technical solution of the present invention, the metasurface is composed of several rectangular metal rings and circular metal patches. The inner and outer metal widths of the rectangular metal ring are 8.6mm and 10mm respectively, and the radii of the circular metal patch increase from the center of the metasurface to the left and right with 2mm and 0.2mm as the initial radius, and the radius increases every two units to the left 0.25mm, the radius of each unit increases by 0.1mm to the right. Rectangular metal rings and circular metal patches are periodically arranged to form a metasurface structure with a length of 10 mm.

As a further improved technical solution of the present invention, the dielectric substrate used for the beam scanning antenna is Rogers4350B, with a relative permittivity of 3.66, a loss tangent of 0.0027, and a thickness of 2.286mm. The dielectric substrate used in the metasurface is Rogers4350B, with a relative permittivity of 3.66, a loss tangent of 0.0027, and a thickness of 0.254mm.

Compared with prior art, the beneficial effect of the present invention:

A wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons of the present invention successfully radiates energy to free space by engraving periodic hole arrays on the upper metal wire of a standard microstrip line , and realize the characteristics of wide bandwidth and wide-angle beam scanning angle; by forming the beam scanning antenna into an antenna array, the gain of the beam scanning antenna is further improved, and the characteristics of high gain are realized; by adding the upper layer of the beam scanning antenna array The metasurface structure further improves the beam scanning angle of the beam scanning antenna array, and realizes a wider angle beam scanning characteristic. Compared with the traditional beam scanning antenna, the antenna structure is more conducive to forming an array, with wider bandwidth, wider beam scanning angle and higher gain.

Description of drawings

FIG. 1 is a schematic structural diagram of a wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons in an embodiment of the present invention;

2 is a unit structure diagram of a beam scanning antenna in a wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons in an embodiment of the present invention;

3 is a unit structure diagram (left) and an array diagram (right) of the metasurface in the wide-angle beam scanning antenna array based on the metasurface and artificial surface plasmons in the embodiment of the present invention;

Fig. 4 is the S-parameter diagram of the simulation with metasurface and without metasurface in the wide-angle beam scanning antenna array based on metasurface and artificial surface plasmon in the embodiment of the present invention;

Fig. 5 is a simulation gain diagram of a wide-angle beam scanning antenna array based on a metasurface and an artificial surface plasmon in an embodiment of the present invention;

Fig. 6 is a comparison diagram of directivity patterns without metasurface (left) and with metasurface (right) at different frequencies in the wide-angle beam scanning antenna array based on metasurface and artificial surface plasmon in the embodiment of the present invention .

Detailed ways:

The following examples further illustrate the content of the present invention, but should not be construed as limiting the present invention. Without departing from the spirit and essence of the present invention, any modifications or replacements made to the structures and parameters of the present invention belong to the scope of the present invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

Example

As shown in Figure 1, a wide-angle beam scanning antenna array based on metasurface and artificial surface plasmons includes two parts: microstrip structure artificial surface plasmon antenna array 1 and metasurface 2. The microstrip artificial surface plasmon antenna array 1 is composed of three microstrip artificial surface plasmon antenna units 3 . The microstrip artificial surface plasmon antenna array 1 is used to generate frequency beam scanning waves, and the generated frequency beam scanning waves further pass through the metasurface to widen the beam scanning angle.

As shown in FIG. 2 , the microstrip artificial surface plasmon antenna unit 3 is composed of a microstrip structure feeding part 4 , a microstrip radiation part 5 with holes in the upper metal line, and a series of metal vias 6 . The artificial surface plasmon antenna array 1 with a microstrip structure is printed on a dielectric substrate 7 .

The microstrip line structure 5 with holes is used to realize the conversion of microstrip line quasi-TEM waves to SSPPs waves (TM waves), so as to realize the characteristics of surface plasmons. Through its high-order mode radiation properties, the bound energy is radiated to free space. A series of metal vias 6 etched in the artificial surface plasmon antenna unit 3 are used to increase the isolation between two adjacent antennas. The gain and other characteristics of the artificial surface plasmon antenna array 1 are improved.

As shown in Fig. 3, the metasurface 2 has a periodic cell structure. Each unit structure includes a rectangular metal ring 8 and a circular metal patch 9 , and the circular metal patch 9 is located in the middle of the rectangular metal ring 8 . The unit structure is printed on the three-layer dielectric substrate 10 to form a four-layer structure. The inner and outer metal widths of the rectangular metal ring 8 are 8.6 mm and 10 mm respectively, and the radius of each circular metal patch 9 increases from the center of the metasurface 2 to the left and to the right with an initial radius of 2 mm and 0.2 mm, respectively. The radius of sheet 9 increases by 0.25mm for every two units to the left, and increases by 0.1mm for each unit to the right to form a metasurface 2 array to widen the beam scanning angle of the antenna.

The distance between the artificial surface plasmon antenna array 1 and the metasurface 2 of the microstrip structure is 10 mm, the width of the artificial surface plasmon antenna 3 is 20 mm, the width of the microstrip feeding part line 4 is 9 mm, and the upper metal wire is micro The radius of the circular hole with the radiating portion 5 is 4.3 mm. The radius of the metal vias 6 is 0.2 mm, and the distance between the metal vias is 0.6 mm.

The dielectric substrate 7 used in the microstrip structure artificial surface plasmon antenna array 1 is Rogers4350B, with a relative permittivity of 3.66, a loss tangent of 0.0027, and a thickness of 2.286mm. The dielectric substrate 10 used in the metasurface 2 is Rogers4350B, with a relative permittivity of 3.66, a loss tangent of 0.0027, and a thickness of 0.254 mm.

Figure 4 shows the S-parameter diagram of the simulation with and without metasurface in the wide-angle beam scanning antenna array based on metasurface and artificial surface plasmon, the abscissa represents the frequency, and the ordinate represents the S parameter, the unit for dB. It can be seen from Figure 4 that the impedance bandwidth of the SSPP antenna array without metasurface can work at about 9-30 GHz, and the addition of the metasurface does not have much influence on the S parameters of the antenna, and the working frequency band is almost unchanged.

Fig. 5 shows the gain diagram of the simulation in the wide-angle beam scanning antenna array based on the metasurface and the artificial surface plasmon. The abscissa represents the frequency, and the ordinate represents the peak gain, and the unit is dBi. It can be seen from Figure 5 that the average gain of the wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons is about 12.8dBi.

Figure 6 is a comparison of the directivity patterns without metasurface (left) and with metasurface (right) at different frequencies in the wide-angle beam scanning antenna array based on metasurface and artificial surface plasmons. As can be seen from the left figure, the beam scanning angle (143°) of the antenna array without the metasurface structure is about -75° to +68° scanning. It can be seen from the figure on the right that after adding the metasurface structure, the beam scanning angle in the low frequency band can be broadened very well, achieving an effect similar to end-fire, and the beam scanning angle can reach 163° scanning (-88 ° to +75°) effect.

Claims (5)

1. Wide-angle beam scanning antenna array based on metasurface and artificial surface plasmon, characterized in that it includes microstrip artificial surface plasmon antenna array (1) and metasurface (2), microstrip artificial surface, etc. The polaritron antenna array (1) includes several antenna units (3), and the antenna unit (3) includes a feeding part (4), a microstrip radiation part with holes in the upper metal line (5) and a number of metal vias (6) , the metal through hole (6) is etched in the antenna unit (3); the artificial surface plasmon antenna array (1) of the microstrip structure is printed on the dielectric substrate one (7); the metasurface (2) has a periodic Unique unit structure, the unit structure is printed on the three-layer dielectric substrate 2 (10), forming a four-layer structure; each unit structure includes a rectangular metal ring (8) and a circular metal patch (9), the circular metal The patch (9) is located in the middle of the rectangular metal ring (8), the rectangular metal rings (8) of each unit structure are the same, and the radius of each circular metal patch (9) is left and right from the center of the metasurface (2) The initial radius is incremented by 2mm and 0.2mm respectively; The antenna unit (3) is fed by the SMA connector, the upper metal wire of the microstrip radiation part (5) is connected to the inner core of the SMA structure, and the lower metal ground of the microstrip radiation part (5) is connected to the outer core of the SMA structure. 2. The wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons according to claim 1, wherein the width of the upper metal line is 9 mm, the width of the lower metal ground is 20 mm, and the upper metal line The radius of the hole in the line is 4.3mm. 3. The wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons according to claim 1, characterized in that, the radius of the metal through hole (6) is 0.2mm, and the metal through hole (6) The distance between them is 0.6mm. 4. The wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons according to claim 1, characterized in that the inner and outer metal widths of the rectangular metal ring (8) are 8.6mm and 10mm respectively, The radius of the circular metal patch (9) increases by 0.25mm every two units to the left, and increases by 0.1mm for each unit to the right, with a thickness of 0.035mm. 5. The wide-angle beam scanning antenna array based on metasurfaces and artificial surface plasmons according to claim 1, characterized in that, the dielectric substrate one (7) is Rogers4350B, the relative permittivity is 3.66, and the loss The tangent is 0.0027, and the thickness is 2.286mm; the second dielectric substrate (10) is Rogers4350B, the relative permittivity is 3.66, the loss tangent is 0.0027, and the thickness is 0.254mm.

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