Beam Reconfigurable Antenna Based on Artificial Surface Plasmons and Wireless Communication System

Abstract

The present invention provides a beam reconfigurable antenna based on artificial surface plasmon polaritons and a wireless communication system in the technical field of reconfigurable antennas, including a dielectric substrate, a metal ground, a reconfigurable feeding network, and an antenna radiation body. The metal ground and the antenna radiation body are connected to the dielectric substrate, and the reconfigurable feeding network is located at one end of the antenna radiation body. By controlling the input voltage of the RF port, the bias state of the PIN diodes in the reconfigurable feeding network can be controlled, so as to adjust the feeding mode of the antenna radiation body, thereby realizing the conversion of the working mode of the antenna radiation body, that is, the antenna can be switched between a horizontal beam and a vertical beam. The present invention realizes the beam reconfigurable performance of the SSPPs antenna, and at the same time maintains the beam stability and high gain of the antenna in each mode within the working frequency band. The antenna has the advantages of simple structure, low cost, stable performance, and can be widely applied in wireless communication, etc.

Description

Technical Field

[0001] The present invention relates to the technical field of reconfigurable antennas, and more specifically, to a beam reconfigurable antenna based on spoof surface plasmon polaritons (SSPPs). Background Art

[0002] With the rapid development of wireless communication technology and limited installation space, in order to ensure the smooth evolution of existing networks and services, existing wireless communication systems usually require antennas to have the ability of beam conversion. However, traditional array antennas need to design complex feeding networks and phase conversion systems, which are large in volume and weight, not conducive to system integration, and usually have high costs. At the same time, due to the mutual coupling between antenna elements, it is usually difficult to achieve high-angle scanning performance. Therefore, beam reconfigurable antennas that can achieve multiple beam conversions have attracted the attention of many researchers due to their low cost and simple structure.

[0003] In 2004, in order to realize surface plasmon polaritons in the optical band in the terahertz and microwave bands, reference [1] (Professor Pendry and his collaborators) constructed a periodic dielectric hole array structure on the metal surface and theoretically proved that a surface wave is confined to propagate on the surface of the structure. The dispersion and sub-wavelength confinement of this surface wave are very similar to those of surface plasmon polaritons, so it is called spoof surface plasmon polaritons (SSPPs). The specific periodic structure that supports this SSPPs mode is also called SSPPs structure (or SSPPs waveguide).

[0004] SSPPs have two basic operating modes. When it operates in the odd-mode, the antenna end-fires and emits a vertical beam. When it operates in the even-mode, the antenna side-fires and emits a horizontal beam. Regarding this operating characteristic, reference 2 realized the conversion between the odd-mode and even-mode operating modes of SSPPs by constructing a reconfigurable circuit controlled by PIN diode switches, thus realizing the beam reconfigurable function of the antenna between vertical and horizontal beams. However, beam reconfigurable antennas designed based on SSPPs usually have problems of narrow operating bandwidth and easy beam deviation within the frequency band. To address this problem, the present invention discloses a novel beam reconfigurable antenna based on SSPPs, which can achieve reconfigurable performance between horizontal and vertical beams within a relatively large frequency band, with stable beam pointing and high gain. Summary of the Invention

[0005] Aiming at the defects in the prior art, the purpose of the present invention is to provide a beam reconfigurable antenna based on spoof surface plasmon polaritons and a wireless communication system.

[0006] A beam reconfigurable antenna based on artificial surface plasmon according to the present invention includes a dielectric substrate, a metal ground, a reconfigurable feeding network, and an antenna radiation body. The metal ground and the antenna radiation body are respectively attached to the lower surface and the upper surface of the dielectric substrate, and the reconfigurable feeding network is located at one end of the antenna radiation body;

[0007] By controlling the bias states of the PIN diodes in the reconfigurable feeding network, the feeding method of the antenna radiation body is adjusted, thereby realizing the conversion of the working mode of the antenna radiation body, and further realizing the switching of the antenna between the horizontal beam and the vertical beam.

[0008] Preferably, the reconfigurable feeding network includes a one-to-two power divider network, a coplanar waveguide to monopole structure, a sector capacitor and a metal via, and a PIN diode. The coplanar waveguide to monopole structure is arranged on the lower surface of the dielectric substrate, and the one-to-two power divider network, the sector capacitor and the metal via, and the PIN diode are arranged on the upper surface of the dielectric substrate;

[0009] One end of the PIN diode is connected to the one-to-two power divider network, and the other end of the PIN diode is connected to the sector capacitor and the metal via.

[0010] Preferably, the PIN diode includes a left PIN diode and a right PIN diode, and the left PIN diode and the right PIN diode are respectively connected to the corresponding sector capacitor and the metal via;

[0011] And the connection directions of the left PIN diode and the right PIN diode to the antenna are opposite.

[0012] Preferably, the sector capacitor and the metal via include a sector capacitor and a metal via. The metal via is located around the center of the sector capacitor, so that one side of the PIN diode has the same voltage as the metal ground.

[0013] Preferably, the antenna radiation body includes a first radiation structure, a second radiation structure, and a diamond patch. The first radiation structure and the second radiation structure are respectively arranged on the upper surface of the dielectric substrate, and the diamond patch is arranged on the lower surface of the dielectric substrate.

[0014] Preferably, the diamond patch is located in the central area of the lower surface of the dielectric substrate.

[0015] Preferably, the first radiation structure and the second radiation structure are arrow-shaped, and the arrow pointing directions of the first radiation structure and the second radiation structure are opposite.

[0016] Preferably, the first radiation structure and the second radiation structure are symmetric with each other along the short side center line of the dielectric substrate.

[0017] Preferably, when the one-to-two power divider network is connected to the positive voltage, the left PIN diode is turned on and the right PIN diode is turned off. The antenna radiation body is excited by the coplanar waveguide-to-monopole structure arranged on the back of the dielectric substrate. The first radiation structure and the second radiation structure operate in the odd mode, and the antenna end-fires to emit a vertical beam.

[0018] When the one-to-two power divider network is connected to the negative voltage, the left PIN diode is turned off and the right PIN diode is turned on. The antenna radiation body is excited by the microstrip line arranged on the front of the dielectric substrate. The first radiation structure and the second radiation structure operate in the even mode, and the antenna side-fires to emit a horizontal beam.

[0019] The present invention also provides a wireless communication system, which adopts the beam reconfigurable antenna based on artificial surface plasmon polaritons.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) By controlling the bias states of the two PIN diodes, the present invention realizes the adjustment of the feeding mode of the antenna radiation body, thereby realizing the conversion of the working mode of the antenna radiation body, and further realizing the switching of the antenna radiation pattern between the horizontal beam and the vertical beam.

[0022] (2) By adjusting the SSPPs radiation structure, the designed antenna can achieve beam conversion within a relatively large frequency band, and the beam pointing is stable without deviation.

[0023] (3) By loading the sector capacitor and the metal through-hole and the design that the connection directions of the two PIN diodes to the antenna are opposite, the present invention simplifies the steps of beam conversion, also simplifies the difficulty of power supply to the PIN diodes, reduces the manufacturing cost, has a simple overall structure and is easy to process. Description of the Drawings

[0024] By reading the detailed description of the non-restrictive embodiments with reference to the following drawings, other features, objects and advantages of the present invention will become more obvious:

[0025] Figure 1 It is an overall schematic diagram of a beam reconfigurable antenna based on artificial surface plasmon polaritons provided by an embodiment of the present invention;

[0026] Figure 2 It is a top view of a beam reconfigurable antenna based on artificial surface plasmon polaritons provided by an embodiment of the present invention;

[0027] Figure 3 It is a rear view of a beam reconfigurable antenna based on artificial surface plasmon polaritons provided by an embodiment of the present invention;

[0028] Figure 4Echo loss simulation results of the input port when the antenna emits a vertical beam provided by the embodiment of the present invention;

[0029] Figure 5 Pattern simulation results of the antenna on the yoz azimuth plane at 5.1 GHz when the antenna emits a vertical beam provided by the embodiment of the present invention;

[0030] Figure 6 Pattern simulation results of the antenna on the yoz azimuth plane at 5.5 GHz when the antenna emits a vertical beam provided by the embodiment of the present invention;

[0031] Figure 7 Pattern simulation results of the antenna on the yoz azimuth plane at 5.9 GHz when the antenna emits a vertical beam provided by the embodiment of the present invention;

[0032] Figure 8 Variation of the vertical gain within the 5 GHz - 6 GHz frequency band when the beam - reconfigurable antenna provided by the embodiment of the present invention emits a vertical beam.

[0033] Figure 9 Echo loss simulation results of the input port when the antenna emits a horizontal beam provided by the embodiment of the present invention;

[0034] Figure 10 Pattern simulation results of the antenna on the xoz azimuth plane at 5.1 GHz when the antenna emits a horizontal beam provided by the embodiment of the present invention;

[0035] Figure 11 Pattern simulation results of the antenna on the xoz azimuth plane at 5.5 GHz when the antenna emits a horizontal beam provided by the embodiment of the present invention;

[0036] Figure 12 Pattern simulation results of the antenna on the xoz azimuth plane at 5.9 GHz when the antenna emits a horizontal beam provided by the embodiment of the present invention;

[0037] Figure 13 Variation of the horizontal gain within the 5 GHz - 6 GHz frequency band when the beam - reconfigurable antenna provided by the embodiment of the present invention emits a horizontal beam;

[0038] Figure 14 Variation of the horizontal direction non - circularity within the 5 GHz - 6 GHz frequency band when the beam - reconfigurable antenna provided by the embodiment of the present invention emits a horizontal beam.

[0039] Reference numerals in the figure:

[0040] Metal ground 1, reconfigurable feeding network 2, power divider network 21 for splitting one into two, coplanar waveguide to monopole structure 22, fan-shaped capacitor and metal via 23, PIN diode 24, antenna radiation body 3, first radiation structure 31, second radiation structure 32, diamond-shaped patch 33. Detailed implementation manners

[0041] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all fall within the protection scope of the present invention.

[0042] Example 1

[0043] A beam reconfigurable antenna based on artificial surface plasmons provided by the present invention, as Figures 1-3 shown, includes a dielectric substrate 0, a metal ground 1, a reconfigurable feeding network 2, and an antenna radiation body 3. The metal ground 1 and the antenna radiation body 3 are respectively attached to the lower surface and the upper surface of the dielectric substrate, and the reconfigurable feeding network 2 is located at one end of the antenna radiation body 3.

[0044] The reconfigurable feeding network 2 includes a power divider network 21 for splitting one into two, a coplanar waveguide to monopole structure 22, a fan-shaped capacitor and metal via 23, and a PIN diode 24. The coplanar waveguide to monopole structure 22 is disposed on the lower surface of the dielectric substrate, and the power divider network 21 for splitting one into two, the fan-shaped capacitor and metal via 23, and the PIN diode 24 are disposed on the upper surface of the dielectric substrate. One end of the PIN diode 24 is connected to the power divider network 21 for splitting one into two, and the other end of the PIN diode 24 is connected to the fan-shaped capacitor and metal via 23. The PIN diode 24 includes a left PIN diode and a right PIN diode, and the connection directions of the left PIN diode and the right PIN diode to the antenna are opposite. The left PIN diode and the right PIN diode are respectively connected to the corresponding fan-shaped capacitor and metal via 23. The fan-shaped capacitor and metal via 23 include a fan-shaped capacitor and a metal via. The metal via is near the center of the fan-shaped capacitor, realizing the same voltage between one side of the PIN diode 24, the metal via 23, and the metal ground 1.

[0045] The antenna radiation body 3 includes a first radiation structure 31, a second radiation structure 32, and a diamond-shaped patch 33. The first radiation structure 31 and the second radiation structure 32 are respectively disposed on the upper surface of the dielectric substrate, and the first radiation structure 31 and the second radiation structure 32 are symmetric with each other along the short-side center line of the dielectric substrate. The diamond-shaped patch 33 is disposed in the central region of the lower surface of the dielectric substrate. The first radiation structure 31 and the second radiation structure 32 are arrow-shaped, with the first half being an SSPPs structure and the second half being a special-shaped patch. Moreover, the arrow-pointing directions of the first radiation structure 31 and the second radiation structure 32 are opposite.

[0046] Working principle: By controlling the bias state of the PIN diode 24 in the reconfigurable feeding network 2, the feeding method of the antenna radiation body 3 is adjusted, thereby realizing the conversion of the working mode of the antenna radiation body 3, and further realizing the switching of the antenna between the horizontal beam and the vertical beam.

[0047] When the one-to-two power divider network 21 is connected to a positive voltage, the left PIN diode is turned on and the right PIN diode is turned off. The antenna radiation body 3 is excited by the coplanar waveguide to monopole structure 22 disposed on the back of the dielectric substrate. The first radiation structure 31 and the second radiation structure 32 operate in the odd mode, and the antenna end-fires to emit a vertical beam.

[0048] When the one-to-two power divider network 21 is connected to a negative voltage, the left PIN diode is turned off and the right PIN diode is turned on. The antenna radiation body 3 is excited by the microstrip line disposed on the front of the dielectric substrate. The first radiation structure 31 and the second radiation structure 32 operate in the even mode, and the antenna side-fires to emit a horizontal beam.

[0049] More specifically, Figure 4 - Figure 8 gives the relevant performance simulation parameters when the example antenna emits a vertical beam. From the simulation results, it can be seen that the antenna works well in the frequency band of 5.1 GHz - 5.9 GHz, and the impedance bandwidth is 800 MHz. The antenna has an obvious vertical beam pointing, has a high antenna gain (>4.6 dBi) in most frequency bands, and has a relatively wide lobe. The gain decreases when the antenna approaches the low-frequency edge frequency point because the current distribution of the monopole disposed on the back of the dielectric substrate is uneven at this frequency point.

[0050] Figure 9 - Figure 14The relevant performance simulation parameters of the example antenna when transmitting a horizontal beam are given. From the simulation results, it can be seen that the antenna works well in the frequency band of 5.1 GHz - 5.9 GHz, and the impedance bandwidth is also 800 MHz. The antenna has an obvious horizontal beam pointing, with basically no deviation within the working frequency band. The antenna has a relatively high antenna gain (>5.6 dBi) in most frequency bands. In addition, the gain variation range of the antenna in the horizontal plane is <5 dB, and the non-circularity is small. It has good working performance.

[0051] Example 2

[0052] The present invention also provides a wireless communication system, which adopts the plasmonic beam reconfigurable antenna based on artificial surface plasmons in Embodiment 1.

[0053] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be understood as a limitation to the present application.

[0054] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A beam reconfigurable antenna based on artificial surface plasmons, characterized in that It includes a dielectric substrate (0), a metal ground (1), a reconfigurable feeding network (2), and an antenna radiation body (3). The metal ground (1) and the antenna radiation body (3) are respectively attached to the lower surface and the upper surface of the dielectric substrate. The reconfigurable feeding network (2) is located at one end of the antenna radiation body (3). By controlling the bias state of the PIN diodes (24) in the reconfigurable feeding network (2), the feeding method of the antenna radiation body (3) is adjusted, thereby realizing the conversion of the working mode of the antenna radiation body (3), and further realizing the switching of the antenna between the horizontal beam and the vertical beam. The reconfigurable feeding network (2) includes a power divider network (21) that divides one into two, a coplanar waveguide to monopole structure (22), a sector capacitor and a metal via hole (23), and PIN diodes (24). The coplanar waveguide to monopole structure (22) is arranged on the lower surface of the dielectric substrate, and the power divider network (21) that divides one into two, the sector capacitor and the metal via hole (23), and the PIN diodes (24) are arranged on the upper surface of the dielectric substrate. One end of the PIN diode (24) is connected to the power divider network (21) that divides one into two, and the other end of the PIN diode (24) is connected to the sector capacitor and the metal via hole (23). The PIN diode (24) includes a left PIN diode and a right PIN diode. The left PIN diode and the right PIN diode are respectively connected to the corresponding sector capacitor and the metal via hole (23). And the connection directions of the left PIN diode and the right PIN diode to the antenna are opposite. The antenna radiation body (3) includes a first radiation structure (31), a second radiation structure (32), and a diamond patch (33). The first radiation structure (31) and the second radiation structure (32) are respectively arranged on the upper surface of the dielectric substrate, and the diamond patch (33) is arranged on the lower surface of the dielectric substrate. When the power divider network (21) that divides one into two is connected to a positive voltage, the right PIN diode is turned on, and the left PIN diode is turned off. The antenna radiation body (3) is excited by the coplanar waveguide to monopole structure (22) arranged on the back of the dielectric substrate. The first radiation structure (31) and the second radiation structure (32) operate in the odd mode, and the antenna end-fires to emit a vertical beam. When the power divider network (21) that divides one into two is connected to a negative voltage, the right PIN diode is turned off, and the left PIN diode is turned on. The antenna radiation body (3) is excited by a microstrip line arranged on the front of the dielectric substrate. The first radiation structure (31) and the second radiation structure (32) operate in the even mode, and the antenna side-fires to emit a horizontal beam.

2. The beam reconfigurable antenna based on artificial surface plasmons according to claim 1, characterized in that, The sector capacitor and the metal via hole (23) include a sector capacitor and a metal via hole. The metal via hole is located around the center of the sector capacitor, so that one side of the PIN diode (24) has the same voltage as the metal ground (1).

3. The beam reconfigurable antenna based on artificial surface plasmon according to claim 1, characterized in that The diamond patch (33) is located in the central area of the lower surface of the dielectric substrate.

4. The beam reconfigurable antenna based on artificial surface plasmons according to claim 1, characterized in that, The first radiation structure (31) and the second radiation structure (32) are arrow-shaped, and the directions pointed by the arrows of the first radiation structure (31) and the second radiation structure (32) are opposite.

5. The beam reconfigurable antenna based on artificial surface plasmon according to claim 1, characterized in that, The first radiation structure (31) and the second radiation structure (32) are symmetric with each other along the short-side center line of the dielectric substrate.

6. A wireless communication system, characterized in that, An artificial surface plasmon-based beam reconfigurable antenna according to any one of claims 1-5 is adopted.

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