A reconfigurable antenna based on dual-port excitation and metasurface loading mode

Abstract

The application provides a reconfigurable antenna based on a dual-port excitation and a super surface loading mode, and belongs to the field of communication.The reconfigurable antenna comprises a dielectric resonator, a non-uniform super surface, a CPW central signal line, a curved microstrip feed line, a feed PCB metal ground and an antenna common ground plate; the dielectric resonator is used for being inserted into a vertical feed PCB plate, the non-uniform super surface is loaded on the upper surface of the dielectric resonator, the CPW central signal line is located on the back of the vertical feed PCB plate, the curved microstrip feed line is located on the front of the vertical feed PCB plate and is used for exciting a horizontal polarization broadside mode, the feed PCB metal ground is printed on the vertical feed PCB plate, and the antenna common ground plate is arranged at the bottom of the dielectric resonator.The application solves the problems of low port isolation, limited radiation gain under a low profile, difficulty in high-order mode suppression and large lateral size of the existing mode reconfigurable antenna.

Description

Technical Field

[0001] This invention belongs to the field of communications, and particularly relates to a reconfigurable antenna based on dual-port excitation and metasurface loading mode. Background Technology

[0002] Faced with increasingly complex indoor multipath propagation and dense wireless communication environments, traditional single-polarization or fixed-radiation mode antennas are no longer sufficient for modern wireless communication systems (such as 5G). NR, Wi The stringent requirements of Fi 6 and AIoT for high reliability and large channel capacity. Mode-reconfigurable antennas, which can flexibly switch between different radiation modes (such as vertically polarized omnidirectional radiation and horizontally polarized lateral directional radiation) within a single physical aperture, can effectively cope with polarization mismatch under complex channels and meet multi-dimensional spatial coverage requirements. Therefore, they have attracted much attention and are widely used in the design of modern smart micro-terminal antennas.

[0003] In recent years, scholars both domestically and internationally have proposed various implementation schemes in the field of mode-reconfigurable antennas. The most common approach is to use multiple ports sharing the same radiator (such as a planar patch or dielectric resonator), achieving mode switching by changing the excitation of different ports. However, in a very small physical space, multiple ports are prone to generating strong near-field electromagnetic coupling, leading to a sharp deterioration in port isolation. This usually requires the introduction of complex decoupling networks, significantly increasing system size and insertion loss. Secondly, to cater to the trend of thinner and lighter terminal devices, many designs simply reduce the antenna profile height, which often results in a reduction in the equivalent radiating aperture. This not only makes it difficult to suppress high-order mode interference but also causes a significant decrease in antenna gain and radiation efficiency. Finally, most existing mode-reconfigurable antennas rely on complex planar feed networks at the bottom layer, occupying a large amount of lateral physical space, which seriously deviates from the development requirement of extreme antenna miniaturization.

[0004] Despite extensive research in polarization diversity and mode reconfiguration, achieving a balance between high port isolation, low profile size, and excellent radiation gain under ultra-compact physical constraints remains a critical technological bottleneck. Metasurfaces, as two-dimensional artificial electromagnetic structures, offer a novel technological approach to improving upon the shortcomings of existing mode-reconfigurable antennas due to their excellent surface impedance tuning and near-field electromagnetic wave manipulation capabilities.

[0005] A review of existing technologies reveals that current mode-reconfigurable antennas still lack a low-cost solution that can simultaneously achieve high port isolation, miniaturization, and high gain. Summary of the Invention

[0006] To address the aforementioned shortcomings in existing technologies, this invention provides a reconfigurable antenna based on dual-port excitation and metasurface loading modes, which solves the problems of low port isolation, limited radiation gain at low profiles, difficulty in suppressing higher-order modes, and large lateral dimensions found in existing reconfigurable antennas.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a reconfigurable antenna based on dual-port excitation and metasurface loading mode, including a dielectric resonator, a non-uniform metasurface, a CPW center signal line, a curved microstrip feed line, a feed PCB metal ground and an antenna common ground plane. The dielectric resonator is used to insert into the vertical feed PCB board. The non-uniform metasurface is loaded on the upper surface of the dielectric resonator. The CPW center signal line is located on the back of the vertical feed PCB board. The curved microstrip feed line is located on the front of the vertical feed PCB board and is used to excite the horizontally polarized side-fire mode. The feed PCB metal ground is printed on the vertical feed PCB board. The antenna common ground plane is set at the bottom of the dielectric resonator.

[0008] Furthermore, the dielectric resonator includes a circular dielectric resonator and a rectangular dielectric resonator.

[0009] Furthermore, in the circular dielectric resonator mode, the non-uniform metasurface is a circular non-uniform metasurface loaded on the upper surface of the circular dielectric resonator for omnidirectional mode radiation, antenna miniaturization, and radiation aperture enhancement. A through slot is provided along the axial direction at the center of the circular dielectric resonator for inserting a vertical feed PCB board. The CPW center signal line is connected upward to the circular non-uniform metasurface. The curved microstrip feed line is fed through the metal ground of the feed PCB to excite the HEM mode of the circular dielectric resonator and generate a horizontally polarized side-firing beam. The metal ground of the feed PCB provides a common reference ground for the CPW center signal line and the curved microstrip feed line. The antenna common ground plane is a circular copper plate installed at the bottom of the circular dielectric resonator to achieve reflection radiation and directional enhancement.

[0010] Furthermore, in the rectangular dielectric resonator mode, nylon screws are arranged around the antenna common ground plane and the rectangular dielectric resonator. The non-uniform metasurface is a square non-uniform metasurface, which is loaded on the upper surface of the rectangular dielectric resonator for omnidirectional mode radiation, frequency downtuning, and gain enhancement. The square non-uniform metasurface acts as a radiator in omnidirectional mode radiation. A through slot is provided in the center of the rectangular dielectric resonator along the thickness direction for inserting a vertical feed PCB board. The CPW center signal line is connected upward to the square non-uniform metasurface to excite the TM mode of the rectangular dielectric resonator, generating a vertically polarized 360° omnidirectional beam. The curved microstrip feed line is coupled and fed through the metal ground of the feed PCB to excite the TE mode of the rectangular dielectric resonator, generating a horizontally polarized high-gain side-firing beam. The metal ground of the feed PCB provides a common reference ground for the CPW center signal line and the curved microstrip feed line. The antenna common ground plane is a square copper plate used to reflect electromagnetic waves and improve radiation efficiency.

[0011] The beneficial effects of this invention are: 1. This invention innovatively applies a center-vertically fed PCB board dual-port orthogonal excitation architecture and non-uniform metasurface loading technology to the design of dielectric resonator antennas, breaking through the structural limitations of traditional planar bottom-fed antennas. This invention naturally blocks near-field coupling paths between modes through physical mechanisms, achieving excellent port isolation; simultaneously, it utilizes metasurfaces to achieve miniaturization of the resonant cavity, expand the equivalent radiation aperture, and effectively suppress higher-order modes. This invention can efficiently achieve coordinated coverage of horizontally polarized side-firing beams and vertically polarized omnidirectional beams within an extremely compact volume, perfectly adapting to the application requirements of modern low-cost smart terminals and complex indoor communication scenarios.

[0012] 2. This invention boasts advantages such as miniaturization, simple structure, low cost, high gain, mode reconfigurability, and high port isolation, making it suitable for various Wi-Fi terminals, IoT smart devices, FTTR systems, and miniaturized wireless communication terminal applications. The invention employs a center-vertically fed PCB board with a double-sided orthogonal feeding architecture, enabling the antenna to independently switch between horizontally polarized side-firing and vertically polarized omnidirectional modes within a single aperture, greatly enriching the antenna's radiation pattern and spatial coverage. A high-dielectric-constant dielectric resonator is used as the core radiator, effectively reducing the antenna's physical size while offering advantages of low loss and high radiation efficiency. A non-uniform metasurface is loaded on top of the dielectric resonator, simultaneously serving as an omnidirectional radiator, a frequency down-regulation load, and a radiation aperture enhancement structure, further improving gain, expanding bandwidth, and suppressing higher-order modes without increasing antenna size. This invention eliminates the need for any active switches, bias circuits, and complex decoupling networks, achieving mode reconfiguration solely through dual-port switching, significantly reducing design complexity and manufacturing costs, and enabling flexible switching of dual-mode radiation patterns.

[0013] 3. This invention is the first to combine center vertical PCB double-sided orthogonal feeding with non-uniform metasurface loading, realizing independent excitation and free switching of horizontal polarization side-fire mode and vertical polarization omnidirectional mode within a single dielectric resonator aperture. It ensures mode orthogonality and high port isolation from a physical mechanism, which can meet the all-round spatial coverage requirements in complex indoor scenarios.

[0014] 4. In the antenna design, a center vertical feed PCB board is inserted inside the dielectric resonator. One side is fed by a curved microstrip feed line to excite the side-fire mode, and the other side is fed by the CPW center signal line to excite the omnidirectional mode. Through the dual-port spatial orthogonal layout, excellent port isolation characteristics can be achieved without any decoupling network, which completely solves the technical problems of high coupling and poor isolation of multi-port antennas.

[0015] 5. In antenna design, a non-uniform metasurface structure is loaded on top of the dielectric resonator, enabling it to simultaneously perform three core functions: participating in radiation as the core radiator in omnidirectional mode, achieving resonant frequency reduction and antenna miniaturization through equivalent capacitive load, and expanding the radiation aperture and improving antenna gain and radiation efficiency by utilizing a multi-slot structure, thus overcoming the bottleneck of difficulty in balancing miniaturization and high performance of low-profile antennas.

[0016] 6. Regardless of whether the dielectric resonator adopts a cylindrical or rectangular structure, the present invention can achieve stable dual-mode radiation, high port isolation, and high gain characteristics. The change in the shape of the dielectric resonator is only an equivalent replacement and does not affect the core inventive idea and technical effect.

[0017] 7. The antenna requires no PIN diodes, RF switches, or DC bias circuits. Mode reconstruction can be completed simply by switching the dual-port operating state. It has a simple structure, low loss, low cost, and strong stability. It achieves high radiation efficiency and excellent mode diversity performance in an ultra-compact size, meeting the large-scale deployment needs of Wi-Fi 6, IoT, FTTR, and 5G miniaturized terminals. Attached Figure Description

[0018] Figure 1 This is a 3D view of the reconfigurable antenna in Embodiment 1 (cylindrical dielectric resonator) of the present invention.

[0019] Figure 2 These are three views of the reconfigurable antenna in Embodiment 1 of the present invention. Figure 2 (a) is a top view. Figure 2 (b) is a side view. Figure 2 (c) is the front view.

[0020] Figure 3 This is a radiation performance diagram of the reconfigurable antenna in Embodiment 1 of the present invention. Figure 3 (a) represents state 1. Figure 3 (b) represents state 2.

[0021] Figure 4 This is a 3D view of the reconfigurable antenna in Embodiment 2 (rectangular dielectric resonator) of the present invention.

[0022] Figure 5 These are three views of the reconfigurable antenna in Embodiment 2 of the present invention. Figure 5 (a) is a top view. Figure 5 (b) is a side view. Figure 5 (c) is the front view.

[0023] Figure 6 This is the reconfigurable antenna bandwidth diagram of Embodiment 2 of the present invention.

[0024] Figure 7 This is a radiation performance diagram of the mode-reconfigurable antenna of Embodiment 2 of the present invention. Figure 7 (a) represents state 1. Figure 7 (b) represents state 2.

[0025] Among them, 1-dielectric resonator, 2-non-uniform metasurface, 3-CPW center signal line, 4-curved microstrip feed line, 5-feed PCB metal ground, 6-antenna common ground plane, 7-nylon screw. Detailed Implementation

[0026] The specific embodiments of the present invention are described below to enable those skilled in the art to understand the present invention. However, it should be understood that the present invention is not limited to the scope of the specific embodiments. For those skilled in the art, various changes are obvious as long as they are within the spirit and scope of the present invention as defined and determined by the appended claims. All inventions utilizing the concept of the present invention are protected.

[0027] Example 1 The technical problems to be solved by this invention are listed below in order of importance: the problem of traditional single-polarization / fixed-mode antennas having limited coverage and weak spatial awareness in complex multipath indoor environments; the problem of multi-port antennas having strong electromagnetic mutual coupling and poor port isolation in compact spaces, requiring additional decoupling networks; the problem of low-profile antennas having small radiating aperture, low gain, and difficulty in suppressing higher-order modes, making it difficult to balance miniaturization and high performance; and the problem of traditional planar feeding occupying a large lateral space, failing to meet the miniaturization requirements of highly integrated communication terminals. Accordingly, the objectives of this invention are as follows: First, to achieve flexible switching between horizontally polarized side-firing mode and vertically polarized omnidirectional mode within the aperture of a single dielectric resonator, thereby improving spatial diversity and environmental adaptability; second, to adopt a dual-port orthogonal feeding architecture on a centrally vertically fed PCB board, which physically suppresses inter-mode coupling and achieves high port isolation without additional decoupling networks; third, to load a non-uniform metasurface 2 on top of the dielectric resonator 1, thereby expanding the radiation aperture and suppressing higher-order modes through surface impedance modulation, achieving high gain and high-efficiency radiation in a low profile; and finally, to integrate the feeding and modulation structures into a vertically interpenetrating vertically fed PCB board, significantly saving lateral space on the base plate and achieving ultra-compact antenna design.

[0028] This invention is based on multi-port excitation technology, using a dielectric resonator 1 as the core radiator, combined with a vertically inserted vertically fed PCB board to form a high-isolation mode-reconfigurable feeding architecture. Based on the non-uniform metasurface 2 loading and the high-efficiency radiation characteristics of the dielectric resonator 1, a low-profile, high-performance radiation enhancement structure is formed. By organically integrating multi-port excitation and non-uniform metasurface 2 loading, a mode-reconfigurable antenna is finally proposed, possessing advantages such as high isolation, high gain, low profile, and ultra-compactness. It can achieve rapid reconfiguration of linearly polarized electromagnetic waves between side-fired directional and vertical omnidirectional modes, meeting the application requirements of intelligent, low-cost, and miniaturized multi-mode antennas.

[0029] Based on the dual-port orthogonal excitation theory, mode diversity principle, and metasurface electromagnetic control technology, this invention proposes a mode-reconfigurable radiation structure based on a vertically fed PCB board with double-sided feeding and a top non-uniform metasurface 2. Two embodiments are provided. The two embodiments differ only in the shape of the dielectric resonator 1 (cylindrical versus rectangular); the feeding method, metasurface control mechanism, and mode switching principle are completely identical, both achieving efficient reconfiguration of side-firing directional modes and omnidirectional radiation modes.

[0030] In this embodiment, the present invention provides a reconfigurable antenna based on dual-port excitation and metasurface loading mode, comprising a dielectric resonator 1, a non-uniform metasurface 2, a CPW center signal line 3, a curved microstrip feed line 4, a feed PCB metal ground 5, and an antenna common ground plane 6; the dielectric resonator 1 is inserted into the vertical feed PCB, the non-uniform metasurface 2 is loaded on the upper surface of the dielectric resonator 1, the CPW center signal line 3 is located on the back of the vertical feed PCB, the curved microstrip feed line 4 is located on the front of the vertical feed PCB and is used to excite the horizontally polarized side-fire mode, the feed PCB metal ground 5 is printed on the vertical feed PCB, and the antenna common ground plane 6 is disposed at the bottom of the dielectric resonator 1. In the circular dielectric resonator mode, the non-uniform metasurface 2 is a circular non-uniform metasurface loaded on the upper surface of the circular dielectric resonator for omnidirectional mode radiation, antenna miniaturization, and radiation aperture enhancement. A through slot is provided along the axial direction at the center of the circular dielectric resonator for inserting a vertical feed PCB board. The CPW center signal line 3 is connected upward to the circular non-uniform metasurface. The curved microstrip feed line 4 is coupled and fed through the feed PCB metal ground 5 to excite the HEM mode of the circular dielectric resonator and generate a horizontally polarized side-firing beam. The feed PCB metal ground 5 provides a common reference ground for the CPW center signal line 3 and the curved microstrip feed line 4. The antenna common ground plane 6 is a circular copper plate installed at the bottom of the circular dielectric resonator to achieve reflection radiation and directional enhancement.

[0031] The detailed structure of the reconfigurable antenna based on the cylindrical dielectric resonator mode is as follows: Figure 1 and 2 As shown, the reconfigurable antenna includes a cylindrical dielectric resonator, a circular non-uniform metasurface, a CPW center signal line 3, a curved microstrip feed line 4, a feed PCB metal ground 5, and an antenna common ground plane.

[0032] In this embodiment, the cylindrical dielectric resonator is made of a high dielectric constant material such as alumina ceramic or zirconia ceramic, with a through slot along the axial direction at its center for insertion into the vertical feed PCB. A circular non-uniform metasurface is loaded on the upper surface of the cylindrical dielectric resonator for omnidirectional mode radiation, antenna miniaturization, and enhanced radiation aperture. The CPW center signal line 3 is located on the back of the vertical feed PCB and is used to excite the vertically polarized omnidirectional mode. The curved microstrip feed line 4 is located on the front of the vertical feed PCB and is used to excite the horizontally polarized side-firing mode. The feed PCB metal ground 5 is printed on the vertical feed PCB and serves as a common reference ground for the CPW center signal line 3 and the curved microstrip feed line 4. The antenna common ground plane 6 is a circular metal ground plane located at the bottom of the cylindrical dielectric resonator to improve radiation directivity and efficiency.

[0033] In this embodiment, the cylindrical dielectric resonator 1 is made of a high dielectric constant and low loss material, such as alumina ceramic or zirconia ceramic. Due to its high dielectric constant, the size of the antenna is effectively reduced, realizing the miniaturization of the antenna design. As the radiator of the antenna, it realizes the transmission and reception of electromagnetic signals. The circular non-uniform metasurface serves as one of the core radiators in omnidirectional mode. At the same time, it achieves frequency downshifting through equivalent capacitive loading and expands the radiation aperture and improves gain using a multi-slot structure. The CPW center signal line 3 is connected upward to the circular non-uniform metasurface to excite the TM of the cylindrical dielectric resonator. The system generates a vertically polarized omnidirectional beam. The curved microstrip feed line 4 is coupled to the feed PCB metal ground 5, which excites the HEM mode of the cylindrical dielectric resonator to generate a horizontally polarized side-firing beam. The feed PCB metal ground 5 provides a common reference ground for the CPW center signal line 3 and the curved microstrip feed line 4, making the dual-port structure independent and the field pattern orthogonal. The antenna common ground plane 6 is a circular copper plate, which is installed at the bottom of the cylindrical dielectric resonator 1 to achieve reflection radiation and directional enhancement. The overall structure is fixed with low-loss adhesive and has no metal fasteners to avoid introducing parasitic interference.

[0034] In this embodiment, the dual-port system achieves high isolation due to field orthogonality, eliminating the need for a decoupling network. By switching between the first and second ports (the double-sided PCB inside the dielectric resonator serves as the power supply structure, with one set of feed lines on the front and one set on the back of the vertical feed PCB, which are independent, non-contacting, and non-overlapping, thus naturally forming two independent ports: the first port is the coaxial cable or SMA connector soldered to the beginning of the curved microstrip feed line 4 on the front; the second port is the coaxial cable or SMA connector soldered to the beginning of the CPW center signal line 3 on the back), it can flexibly switch between side-firing directional mode and omnidirectional radiation mode, exhibiting stable radiation performance within the 2.4GHz WiFi band, suitable for the multi-scenario coverage needs of IoT and indoor smart terminals.

[0035] In this embodiment, in the reconfigurable antenna embodiment of the cylindrical dielectric resonator mode, a central vertical PCB double-sided feeding structure is proposed, utilizing the concept of orthogonal field vector space. The front side uses a curved microstrip feed line 4, and the back side uses a CPW center signal line 3. These two feeding structures are independent and orthogonal in polarization, thereby exciting two non-interfering radiation modes within a single radiating aperture. The dielectric resonator 1, as the radiator of the antenna, is made of a material with a high dielectric constant, such as alumina ceramic or zirconia ceramic, to achieve antenna miniaturization. The vertical feeding PCB is inserted from the central slot of the cylindrical dielectric resonator, and the curved microstrip feed line 4 is coupled and fed through the slot of the metal ground of the vertical feeding PCB, exciting the HEM-type mode of the cylindrical dielectric resonator and radiating a horizontally polarized side-firing directional beam. The CPW center signal line 3 on the back side extends upward and connects to the top non-uniform metasurface, exciting the TM-type mode of the cylindrical dielectric resonator and radiating a vertically polarized omnidirectional beam.

[0036] A circular non-uniform metasurface is loaded on top of the antenna, serving three purposes: First, it acts as a core radiator to generate an omnidirectional beam. When energy is fed into the center of the dielectric resonator 1 from the CPW center signal line 3 on the vertical feed PCB, the circular non-uniform metasurface, connected to the top of the center feed line, acts as a radiating surface similar to a top-loaded monopole. Second, it modulates the equivalent impedance and shifts the frequency downward. By introducing an equivalent capacitive load, the resonant frequency is shifted to a lower frequency, further compressing the antenna size. Third, the multi-slot structure enhances the radiation aperture by exciting an open electric field, expanding the equivalent radiation aperture and improving gain. The metal ground 5 of the feed PCB provides a transmission reference ground for both the CPW center signal line 3 and the curved microstrip feed line 4. A common ground plane 6 is installed at the bottom of the antenna to reflect electromagnetic waves and improve radiation efficiency. The overall structure is fixed with low-loss dielectric adhesive to avoid introducing metal parasitic interference.

[0037] Because the electric field vectors of the two modes are strictly orthogonal in space, there is no energy coupling between the modes. Therefore, the two-port configuration naturally possesses high isolation, eliminating the need for an additional decoupling network. By switching the feed states of the first and second ports, it is possible to freely switch between side-firing directional and omnidirectional radiation. This embodiment features a simple structure, extremely low profile, and excellent isolation, with radiation performance as described above. Figure 3 As shown, stable dual-mode coverage is achieved within the 2.45 GHz WLAN band, which can meet the multi-scenario coverage needs of IoT and indoor smart terminals.

[0038] Example 2 This invention provides a reconfigurable antenna based on dual-port excitation and metasurface loading modes, comprising a dielectric resonator 1, a non-uniform metasurface 2, a CPW center signal line 3, a curved microstrip feed line 4, a feed PCB metal ground 5, and an antenna common ground plane 6. In the rectangular dielectric resonator mode, nylon screws 7 are arranged around the antenna common ground plane 6. The non-uniform metasurface 2 is a square non-uniform metasurface, loaded on the upper surface of the rectangular dielectric resonator, used for omnidirectional mode radiation, frequency downtuning, and gain enhancement. The square non-uniform metasurface acts as a radiator in omnidirectional mode radiation, while the rectangular dielectric resonator... A through slot is provided at the center of the resonator along the thickness direction for insertion into the vertical feed PCB. The CPW center signal line 3 is connected upward to the square non-uniform metasurface to excite the TM mode of the rectangular dielectric resonator, generating a vertically polarized 360° omnidirectional beam. The curved microstrip feed line 4 is coupled and fed through the metal ground of the feed PCB 5 to excite the TE mode of the rectangular dielectric resonator, generating a horizontally polarized high-gain side-firing beam. The metal ground of the feed PCB 5 provides a common reference ground for the CPW center signal line 3 and the curved microstrip feed line 4. The antenna common ground plane 6 is a square copper plate used to reflect electromagnetic waves and improve radiation efficiency.

[0039] In this embodiment, the detailed structure of the reconfigurable antenna based on the rectangular dielectric resonator mode is as follows: Figure 4 and 5 As shown, it includes a rectangular dielectric resonator, a square non-uniform metasurface, a CPW center signal line 3, a curved microstrip feed line 4, a feed PCB metal ground 5, an antenna common ground plane 6, and a nylon screw 7.

[0040] The rectangular dielectric resonator is made of a high dielectric constant material such as alumina ceramic or zirconia ceramic, with a through slot in the center along the thickness direction for insertion into the vertical feed PCB. A square non-uniform metasurface is loaded on the upper surface of the rectangular dielectric resonator for omnidirectional mode radiation, frequency downtuning, and gain enhancement. The CPW center signal line 3 is located on the back of the vertical feed PCB and is used to excite the vertically polarized omnidirectional mode. The curved microstrip feed line 4 is located on the front of the vertical feed PCB and is used to excite the horizontally polarized side-fire mode. The feed PCB metal ground 5 is printed on the vertical feed PCB and serves as the reference ground for both the CPW center signal line 3 and the curved microstrip feed line 4. The antenna common ground plane 6 is a square metal ground plane located at the bottom of the rectangular dielectric resonator. The nylon screws 7 are standard nylon screws with a diameter of 3mm, arranged around the rectangular dielectric resonator and the antenna common ground plane 6, totaling four screws, for support and fixation of the antenna structure.

[0041] In this embodiment, the rectangular dielectric resonator is made of a high dielectric constant and low loss material, such as alumina ceramic or zirconia ceramic. Due to its high dielectric constant, the size of the antenna is effectively reduced, achieving a miniaturized antenna design. It serves as the radiator for transmitting and receiving electromagnetic signals. The square non-uniform metasurface directly acts as the radiator in omnidirectional mode. Simultaneously, the equivalent capacitive loading lowers the resonant frequency, and the multi-slot expansion of the radiation aperture enhances the side-fire mode gain. The CPW center signal line 3 connects upwards to the square non-uniform metasurface, exciting the TM mode of the rectangular dielectric resonator. A vertically polarized 360° omnidirectional beam is generated; the curved microstrip feed line 4, coupled to the feed PCB metal ground 5, excites the TE mode of the rectangular dielectric resonator to generate a horizontally polarized high-gain side-firing beam; the feed PCB metal ground 5 provides a common reference ground for the double-sided feed structure, enabling natural high isolation between the two ports; the antenna common ground plane 6 is a square copper plate, installed at the bottom of the rectangular dielectric resonator, used to reflect electromagnetic waves and improve radiation efficiency; the nylon screws 7 consist of four standard metric nylon screws with a diameter of 3mm, used for structural fastening without generating electromagnetic interference.

[0042] In this embodiment, the antenna dual-port isolation is better than -20 dB, and the overlap impedance bandwidth fully covers the 2.4-2.48 GHz WiFi band. It achieves the comprehensive advantages of high isolation, high gain, low profile and mode reconfigurability in an ultra-compact structure, and is suitable for 5G, WiFi 6, FTTR and miniaturized smart wireless communication devices.

[0043] In this embodiment, as Figure 4 and 5 As shown, in the reconfigurable antenna embodiment of the rectangular dielectric resonator mode, the principle of center vertical PCB double-sided feeding + top metasurface loading, which is completely consistent with that of Embodiment 1, is adopted. Only the dielectric resonator 1 is changed from a cylinder to a rectangle, and the non-uniform metasurface 2 and the antenna common ground plane 6 are changed to squares accordingly to achieve structural matching. The dielectric resonator 1, as the radiator of the antenna, is made of high dielectric constant and low loss ceramic material to further improve the antenna efficiency and gain. The vertical feeding PCB is inserted from the center slot of the rectangular dielectric resonator, and the curved microstrip feed line 4 is coupled through the metal ground 5 of the feeding PCB to excite the TE mode of the rectangular dielectric resonator, forming a high-gain horizontally polarized side-firing beam. The center signal line 3 of the CPW on the back side excites the TM mode of the rectangular dielectric resonator to form a 360° uniform vertically polarized omnidirectional beam.

[0044] The top square non-uniform metasurface serves three main functions: first, it acts as the core radiator to generate an omnidirectional beam, directly participating in radiation in omnidirectional mode and acting as a top-loaded monopole radiating surface; second, it serves as an equivalent capacitive load to achieve antenna miniaturization and shift the resonant frequency to lower frequencies; and third, it expands the radiating aperture and improves gain and radiation efficiency. The feed PCB metal ground 5 provides a reference ground for both the CPW center signal line 3 and the curved microstrip feed line 4, while the bottom antenna common ground plane 6 ensures radiation directivity. The entire structure is secured with nylon screws, ensuring structural stability and eliminating electromagnetic interference.

[0045] In this embodiment, the dual-port antenna achieves high isolation due to field orthogonality, with port isolation better than -20dB within the operating frequency band. By switching between different ports, the antenna can seamlessly switch between two modes. Its S-parameters and radiation performance are as follows: Figure 6 , Figure 7 As shown, the antenna's overlap -10 dB impedance bandwidth fully covers the 2.4-2.48 GHz WLAN band, meeting the operating frequency requirements of 5G communication systems and IoT systems. This invention achieves a comprehensive advantage of high isolation, high gain, low profile, and mode reconfigurability within an ultra-compact size. Figure 6 In this equation, S11 represents the input reflection coefficient; S22 represents the output reflection coefficient; and S12 represents the reverse transmission coefficient.

[0046] In summary, this invention presents a reconfigurable antenna based on dual-port excitation and metasurface loading modes, which boasts advantages such as miniaturization, simple structure, low cost, high gain, mode reconfigurability, and high port isolation. It is suitable for various Wi-Fi terminals, IoT smart devices, FTTR systems, and miniaturized wireless communication terminal applications. The invention employs a center-vertical PCB double-sided orthogonal feeding architecture, enabling the antenna to independently switch between horizontally polarized side-firing and vertically polarized omnidirectional modes within a single aperture, greatly enriching the antenna's radiation pattern and spatial coverage. Furthermore, this invention utilizes a high-dielectric-constant dielectric harmonic... The resonator 1, as the core radiator, effectively reduces the physical size of the antenna while bringing advantages of low loss and high radiation efficiency. In this invention, a non-uniform metasurface 2 is loaded on the top of the dielectric resonator 1, making it simultaneously an omnidirectional mode radiator, a frequency down-regulation load, and a radiation aperture enhancement structure. This further improves the gain, expands the bandwidth, and suppresses higher-order modes without increasing the antenna volume. This invention does not require any active switches, bias circuits, or complex decoupling networks. Mode reconstruction can be achieved simply through dual-port switching, greatly reducing design complexity and manufacturing costs, and enabling flexible switching of dual-mode radiation patterns.

Claims

1. A reconfigurable antenna based on dual-port excitation and metasurface loading modes, characterized in that, It includes a dielectric resonator (1), a non-uniform metasurface (2), a CPW center signal line (3), a curved microstrip feed line (4), a feed PCB metal ground (5), and an antenna common ground plane (6). The dielectric resonator (1) is used to insert into the vertical feed PCB board. The non-uniform metasurface (2) is loaded on the upper surface of the dielectric resonator (1). The CPW center signal line (3) is located on the back of the vertical feed PCB board. The curved microstrip feed line (4) is located on the front of the vertical feed PCB board and is used to excite the horizontally polarized side-fire mode. The feed PCB metal ground (5) is printed on the vertical feed PCB board. The antenna common ground plane (6) is set at the bottom of the dielectric resonator (1).

2. The reconfigurable antenna based on dual-port excitation and metasurface loading mode according to claim 1, characterized in that, The dielectric resonator (1) includes a circular dielectric resonator and a rectangular dielectric resonator.

3. The reconfigurable antenna based on dual-port excitation and metasurface loading mode according to claim 2, characterized in that, In the circular dielectric resonator mode, the non-uniform metasurface (2) is a circular non-uniform metasurface, which is loaded on the upper surface of the circular dielectric resonator for omnidirectional mode radiation, antenna miniaturization and radiation aperture enhancement; a through slot is provided along the axial direction at the center of the circular dielectric resonator for inserting a vertical feed PCB board; the CPW center signal line (3) is connected upward to the circular non-uniform metasurface; the curved microstrip feed line (4) is coupled and fed through the feed PCB metal ground (5) to excite the HEM mode of the circular dielectric resonator and generate a horizontally polarized side-firing beam; the feed PCB metal ground (5) provides a common reference ground for the CPW center signal line (3) and the curved microstrip feed line (4); the antenna common ground plane (6) is a circular copper plate, which is installed at the bottom of the circular dielectric resonator to realize reflection radiation and directional enhancement.

4. The reconfigurable antenna based on dual-port excitation and metasurface loading mode according to claim 2, characterized in that, In the rectangular dielectric resonator mode, the antenna common ground plane (6) and the rectangular dielectric resonator are surrounded by nylon screws (7); the non-uniform metasurface (2) is a square non-uniform metasurface, which is loaded on the upper surface of the rectangular dielectric resonator for omnidirectional mode radiation, frequency down-tuning and gain enhancement. The square non-uniform metasurface acts as a radiator in omnidirectional mode radiation. A through slot is provided in the center of the rectangular dielectric resonator along the thickness direction for inserting the vertical feed PCB board. The CPW center signal line (3) is connected upward to the square non-uniform metasurface to excite the TM mode of the rectangular dielectric resonator and generate a vertically polarized 360° omnidirectional beam. The curved microstrip feed line (4) is coupled and fed through the feed PCB metal ground (5) to excite the TE mode of the rectangular dielectric resonator and generate a horizontally polarized high-gain side-firing beam. The feed PCB metal ground (5) provides a common reference ground for the CPW center signal line (3) and the curved microstrip feed line (4). The antenna common ground plane (6) is a square copper plate for reflecting electromagnetic waves and improving radiation efficiency.

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