Vertical polarization directional diagram reconfigurable antenna

Abstract

The invention provides a vertical polarization directional diagram reconfigurable antenna which is provided with a dielectric substrate I serving as a supporting base, and a dielectric substrate II and a dielectric substrate III which are of a cross structure are fixedly arranged in the center of the upper end face of the dielectric substrate I; a crossed elliptical monopole is arranged at the central position of the crossed dielectric substrate II and dielectric substrate III; the dielectric substrate II is provided with a zigzag line parasitic structure I and a zigzag line parasitic structure II which are bilaterally symmetrical; the dielectric substrate III is provided with a zigzag line parasitic structure III and a zigzag line parasitic structure IV which are bilaterally symmetrical; the center of the zigzag line parasitic structure I is provided with a PIN switching diode D1, the center of the zigzag line parasitic structure II is provided with a PIN switching diode D2, the center of the zigzag line parasitic structure III is provided with a PIN switching diode D3, and the center of the zigzag line parasitic structure IV is provided with a PIN switching diode D4. The dielectric substrate I1 is used for etching a direct current bias line; and the dielectric substrate II etches the rectangular ground. The antenna is simple in structure, facilitates integration, can achieve multi-beam switching and wide working frequency band at the same time, and is suitable for popularization.

Description

Technical Field

[0001] This invention belongs to the field of electrical microwave antenna technology, specifically relating to a vertically polarized pattern reconfigurable antenna. Background Technology

[0002] Reconfigurable antennas achieve dynamic reconfiguration of antenna performance primarily by adjusting state-variable devices. Within the same physical aperture size, these antennas can reconfigure their electrical parameters by changing the current distribution on the antenna aperture surface, essentially allowing multiple antennas to share a single physical aperture in a time-division multiplexing manner. Reconfigurable antennas mainly include four types: frequency-reconfigurable, polarization-reconfigurable, pattern-reconfigurable, and hybrid-reconfigurable antennas. Among them, pattern-reconfigurable antennas can adjust their radiation beam in real time according to environmental changes to achieve optimal radiation performance. They can enhance signal strength in the target direction while reducing signal strength in interference directions, thereby reducing electromagnetic interference in the environment and improving signal effectiveness and communication quality. The advantage of pattern-reconfigurable antennas is that one antenna can replace the performance of multiple traditional antennas, which not only reduces the number of antennas in a communication system but also significantly reduces antenna manufacturing costs.

[0003] A Yagi antenna consists of an active excitation element, a reflector, and several directors, offering advantages such as simple structure, strong directivity, and high gain. Its working mechanism is as follows: the active excitation element acts as the primary radiator, emitting electromagnetic waves under excitation, while passive elements, acting as parasitic components, influence the radiation direction of the active element. The active element is typically designed as a half-wavelength resonator, with the spacing between the passive and active elements slightly less than a quarter wavelength. By changing the length of the passive elements, different characteristics can be observed. When the length of the passive element is slightly greater than half a wavelength, it exhibits inductive characteristics, acting as a reflector and enhancing the radiation pattern on the active element side. When the length of the passive element is slightly less than half a wavelength, it exhibits capacitive characteristics, acting as a director and further enhancing the radiation pattern on the active element side. Due to its ability to generate directional radiation, the Yagi-like antenna structure is well-suited for designing multi-beam switchable pattern reconfigurable antennas. In 2023, J. LU et al. published "A Yagi Antenna with a Pattern Reconfigurable Based on Active Corrugated Stripline" in IEEE Transactions on Antennas and Propagation, proposing a design method for a pattern reconfigurable Yagi antenna based on Active Corrugated Stripline (ACSL) technology. A traditional dipole is used as the driving element, with a pair of ACSLs in different states symmetrically placed on either side of the dipole. The ACSLs in different states have different average phase constants (βave), with the ACSL with the lower βave acting as a director and the other as a reflector. By changing the βave of the ACSLs, a Yagi antenna with a reconfigurable front and rear pattern is achieved. This antenna features a compact design with physical dimensions of 0.42λ0 × 0.42λ0, and stably performs dual-beam switching within 8.3% of the relative bandwidth. However, existing pattern reconfigurable antennas are complex in structure, difficult to integrate, and struggle to simultaneously achieve multiple beam switching and a wide operating bandwidth. Therefore, the following improved technical solution is proposed. Summary of the Invention

[0004] The technical problem solved by this invention is to provide a vertically polarized pattern reconfigurable antenna, which solves the technical problems of existing pattern reconfigurable antennas having complex structures, being difficult to integrate, and being unable to simultaneously achieve multiple beam switching and a wide operating frequency band.

[0005] The technical solution adopted in this invention is as follows: A vertically polarized pattern reconfigurable antenna, comprising a dielectric substrate I, which serves as a supporting base, with a cross-shaped dielectric substrate II and dielectric substrate III fixedly positioned at the center of its upper surface; the center of the cross-shaped dielectric substrates II and III has a cross-shaped elliptical monopole; the dielectric substrate II has a left-right symmetrical zigzag parasitic structure I and a zigzag parasitic structure II; the dielectric substrate III has a left-right symmetrical zigzag parasitic structure III and a zigzag parasitic structure IV; the center of the zigzag parasitic structure I has a PIN switching diode D1, the center of the zigzag parasitic structure II has a PIN switching diode D2, the center of the zigzag parasitic structure III has a PIN switching diode D3, and the center of the zigzag parasitic structure IV has a PIN switching diode D4; a DC bias line is etched on the dielectric substrate I; and a rectangular ground plane is etched on the dielectric substrate II.

[0006] In the above technical solution, the dielectric substrate I has a cross-shaped slot at its center, and the dielectric substrate II and dielectric substrate III 3 are fixed in the cross-shaped slot.

[0007] In the above technical solution, a circular through hole is further provided at the center of the cross-shaped slot.

[0008] In the above technical solution, further: elliptical monopole I is etched on the front side of dielectric substrate II; elliptical monopole II is etched on the front side of dielectric substrate III; an elongated rectangular slit is formed at the upper end of elliptical monopole I; a short rectangular slit is formed at the lower end of elliptical monopole II; dielectric substrate II and dielectric substrate III are connected and adapted through the elongated rectangular slit and the short rectangular slit to form the cross-shaped elliptical monopole.

[0009] In the above technical solution, further: the elliptical monopole I is provided with symmetrical tortuous parasitic structure I and tortuous parasitic structure II on the left and right sides; the elliptical monopole II is provided with tortuous parasitic structure III and tortuous parasitic structure IV on the left and right sides.

[0010] In the above technical solution, further: PIN switching diodes D1 and D2 are respectively provided at the center connection of the tortuous parasitic structure I and the tortuous parasitic structure II; the DC bias circuit I provided on the dielectric substrate II conducts PIN switching diodes D1 and D2; PIN switching diodes D3 and D4 are respectively provided at the center connection of the tortuous parasitic structure III and the tortuous parasitic structure IV; the DC bias circuit II provided on the dielectric substrate III conducts PIN switching diodes D3 and D4.

[0011] In the above technical solution, further: a positive DC bias line I is provided on the center line of each of the tortuous line parasitic structures I and II; a positive DC bias line II is provided on the center line of each of the tortuous line parasitic structures III and IV; a rectangular ground plane and two negative DC bias lines I are etched on the back side of the dielectric substrate II; two negative DC bias lines II are etched on the back side of the dielectric substrate III.

[0012] In the above technical solution, the antenna further includes the following: under vertical polarization, the antenna achieves eight beam switching at 45° intervals, the antenna operating bandwidth covers 1.96 to 2.62 GHz, and the maximum gain of the operating bandwidth is 5.5 dBi.

[0013] In the above technical solution, the dielectric substrate I, dielectric substrate II, and dielectric substrate III of the antenna are made of dielectric materials with a dielectric constant of 4.4±0.2 and a loss tangent of no more than 0.025, and the reconfigurable switching of the beam is achieved through specific thickness distribution.

[0014] In the above technical solution, further: the dielectric substrate I, dielectric substrate II, and dielectric substrate III are all made of FR4 material; the thickness of dielectric substrate I is 2mm, and the thickness of dielectric substrate II and dielectric substrate III is 1.6mm.

[0015] Advantages of this invention compared to existing technologies: 1. The pattern reconfigurable antenna designed in this invention uses a cross-elliptical monopole antenna as the main radiating structure. Compared with a single elliptical monopole, the cross-elliptical monopole radiates energy more evenly in all directions to ensure the stability and consistency of the pattern in all states.

[0016] 2. This invention innovatively designs a tortuous parasitic structure, reducing the height of the reflector to 0.21λ0, and achieving a total antenna height of 0.33λ0; compared with the traditional three-element Yagi antenna, the reflector length is greater than 0.5λ0, and the antenna profile height is significantly reduced.

[0017] 3. In this invention, a DC bias circuit is provided on the dielectric substrate, and an inductor is used to prevent radio frequency current from passing through the DC line; in order to make the two diodes D3 and D4 conduct, a DC bias circuit is designed on the dielectric substrate, and an inductor is used to prevent radio frequency current from passing through the DC bias line; due to the approximate symmetry of the antenna structure, the beam switching mechanism of states 1 / 3 / 5 / 7 is the same, and all of them operate in the three-reflection mode; the beam switching mechanism of states 2 / 4 / 6 / 8 is also the same, and all of them operate in the double-reflection mode.

[0018] 4. The vertical polarization pattern reconfigurable antenna of the present invention achieves flexible pattern reconfiguration, preservation of vertical polarization characteristics, compact integration, low cost, high reliability and multi-scenario adaptability through innovative design of dielectric substrate and parasitic structure, combined with dynamic control of PIN switching diode.

[0019] 5. The innovative design of the cross-shaped slot and circular through-hole in this invention, along with the embedded design of the dielectric substrate, enhances convenience and installation flexibility. The circular through-hole design ensures power supply accuracy, improves radiation efficiency and bandwidth potential, and the synergy between the slot and parasitic structure enhances the accuracy of radiation pattern reconstruction and multi-mode capability. Standardized processing reduces costs and improves yield and production efficiency. Stress dispersion and heat dissipation design ensure long-term reliability in harsh environments. This invention achieves comprehensive optimization in structure, performance, cost, and adaptability, providing an efficient solution for demanding scenarios such as 5G / 6G communication, satellite navigation, and smart sensors.

[0020] 6. This invention provides a vertically polarized pattern reconfigurable antenna. Elliptical monopoles I and II are etched on dielectric substrates II and III, respectively. Long and short rectangular slots are designed for interlocking, forming cross-shaped elliptical monopoles. This achieves comprehensive optimization in performance, structure, cost, and adaptability, providing an efficient solution for high-bandwidth, multi-scenario communication. It offers broadband and multi-band coverage, dynamic pattern reconfiguration, and strong beam scanning and sidelobe suppression capabilities. The interlocking design reduces size, improving portability and installation flexibility. Standardized processing reduces costs and improves yield and production efficiency.

[0021] 7. The parasitic structures I-IV of this invention, as extensions of the radiator, can generate multiple resonant points with their tortuous shape, forming a composite radiation mode with the elliptical monopoles I and II. By adjusting the length, width, and tortuosity of the parasitic structures, the surface current distribution can be precisely controlled, thereby changing the beamwidth, pointing, and sidelobe level of the radiation pattern. The left-right symmetrical parasitic structures can generate a symmetrical radiation field, avoiding radiation pattern shift. At the same time, by independently controlling each group of parasitic structures, symmetrical scanning or asymmetrical modulation of the beam can be achieved.

[0022] 8. This invention achieves dynamic control of radiation characteristics and functional expansion by designing symmetrical tortuous parasitic structures on both sides of elliptical monopoles I and II, and integrating PIN switching diodes and DC bias circuits. The innovative design of the tortuous parasitic structure and PIN switching diodes enables the antenna to achieve a comprehensive breakthrough in performance, structure, cost and adaptability, providing an efficient solution for high-bandwidth, multi-scenario communication, and is especially suitable for high-end application fields such as smart terminals, vehicle communication, and satellite navigation.

[0023] 9. This invention integrates a positive DC bias line into the center line of a parasitic tortuous structure and designs a rectangular ground plane and a negative DC bias line on the back of the dielectric substrate, thereby achieving deep integration of the DC bias circuit and the radio frequency structure. It has high bias efficiency, compact structure, complete signal, and is feasible to manufacture.

[0024] 10. This invention features multi-beam switching capability, enhancing spatial coverage and communication flexibility. The antenna achieves eight beam switching at 45° intervals, effectively dividing the 360° space into eight independent directions, with each beam capable of independently adjusting its radiation direction. In base station applications, it can cover a wider area and reduce blind spots. In radar or satellite communications, it can track moving targets by rapidly switching beams, improving system response speed. The beam switching function allows the antenna to dynamically adjust its radiation direction based on user location or signal strength, optimizing signal quality.

[0025] 11. This invention achieves an optimal balance between cost, process, performance and flexibility by combining FR4 material with thickness-differentiated design. It is especially suitable for communication scenarios that are cost-sensitive and require large-scale deployment, such as 5G base stations and IoT devices, while meeting the requirements of multi-beam switching and high gain in the 1.96 to 2.62 GHz frequency band. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the antenna of the present invention; Figure 2 for Figure 1 Front view of dielectric substrate I; Figure 3 for Figure 1 Front view of dielectric substrate II; Figure 4 for Figure 1 Front view of dielectric substrate III; Figure 5 This is a 3D radiation pattern of the antenna simulation for this invention; Figure 6(a) shows the simulated reflection coefficients of the antenna in all states; Figure 6(b) shows the measured reflection coefficients of the antenna in all states; Figure 7 The antenna gain of this invention is the result of both simulation and actual measurement. Figure 8 The simulation efficiency of the antenna of this invention under all states; Figure 9(a) shows the simulated H-plane radiation pattern of the antenna of the present invention at the center frequency in states 1 / 3 / 5 / 7; Figure 9(b) shows the simulated H-plane radiation pattern of the antenna of the present invention at the center frequency under state 2 / 4 / 6 / 8. Figure 10(a) is a simulation diagram of the H-plane of the antenna of the present invention at the center frequency in state 1 / 3; Figure 10(b) shows the measured radiation pattern of the antenna of the present invention in state 2 / 4. Figure 11(a) shows the simulated radiation pattern of the antenna of the present invention at the center frequency in state 1 / 3. Figure 11(b) shows the simulated radiation pattern of the antenna of the present invention at the center frequency in state 2 / 4. In the figure: 1-Dielectric substrate I, 101-Cross slot, 102-Circular through hole, 2-Dielectric substrate II, 3-Dielectric substrate III, 4-Elliptical monopole, 21-Zigzag parasitic structure I, 22-Zigzag parasitic structure II, 31-Zigzag parasitic structure III, 32-Zigzag parasitic structure IV, 11-DC bias line, 25-Rectangular ground plane, 41-Elliptical monopole I, 42-Elliptical monopole II, 411-Long rectangular slot, 421-Short rectangular slot. Detailed Implementation

[0027] The following will refer to the appendices in the embodiments of the present invention. Figure 1-1 1. The technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] A vertically polarized pattern reconfigurable antenna includes a dielectric substrate I1, which serves as a support base. A cross-shaped dielectric substrate II2 and a dielectric substrate III3 are fixedly mounted at the center of the upper surface of the dielectric substrate I1. The cross-shaped dielectric substrates II2 and III3 have cross-shaped elliptical monopoles 4 at their centers. The dielectric substrate II2 has two symmetrical zigzag parasitic structures: I21 and II22. The dielectric substrate III3 has two symmetrical zigzag parasitic structures III31 and IV32. A PIN diode D1 is located at the center of zigzag parasitic structure I21, a PIN diode D2 at the center of zigzag parasitic structure II22, a PIN diode D3 at the center of zigzag parasitic structure III31, and a PIN diode D4 at the center of zigzag parasitic structure IV32. A DC bias line 11 is etched on the dielectric substrate I1, and a rectangular ground plane 25 is etched on the dielectric substrate II2.

[0029] It should be noted that existing pattern-reconfigurable antennas have complex structures, which are not conducive to integration and make it difficult to simultaneously achieve multiple beam switching and a wide operating bandwidth. The reflector length of traditional ternary Yagi antennas is still quite large, making it difficult to meet the requirements of a compact structure. This invention innovatively designs a tortuous parasitic structure, reducing the reflector height to 0.21λ0, achieving a total antenna height of 0.33λ0. By flexibly controlling the connectivity of the tortuous parasitic structure using a PIN diode switch, the functions of the reflector and director are switched. Furthermore, the distance between the parasitic structure and the monopole is much less than 1 / 4λ, further ensuring the overall compactness of the antenna structure.

[0030] Therefore, this invention has significant advantages in terms of structural complexity, requiring fewer PIN switching diodes, while also achieving excellent performance such as wide bandwidth, multi-beam switching, and no gain dead zone. This invention's vertically polarized pattern reconfigurable antenna, through innovative design of the dielectric substrate and parasitic structure, combined with dynamic control of PIN switching diodes, achieves flexible pattern reconfiguration, preservation of vertical polarization characteristics, compact integration, low cost, high reliability, and adaptability to multiple scenarios.

[0031] Specifically, by controlling the on / off state of four PIN diodes (D1-D4), the current distribution of the zigzag parasitic structure (Ⅰ21, Ⅱ22, Ⅲ31, Ⅳ32) is altered, thereby adjusting the current path on the antenna surface and achieving dynamic reconstruction of the radiation pattern. Flexible beam pointing: Different radiation states can be switched, aligning the main beam with the target direction while aligning sidelobes or nulls with interference sources, significantly improving anti-interference capabilities. Optimized coverage: Through beam scanning (e.g., 360° coverage capability), energy is rationally allocated, reducing interference to other parts of the communication system and improving overall system efficiency.

[0032] The vertical polarization characteristic enables efficient signal transmission. The antenna employs a vertical polarization design, with the electric field vector perpendicular to the ground. This offers significant advantages in mobile and satellite communications. Vertical polarization matches the antenna polarization of mobile devices (such as mobile phones), reducing polarization mismatch losses and improving signal reception quality. Vertically polarized signals are less prone to generating polarization currents during propagation, reducing energy attenuation caused by ground reflections, ensuring long-distance transmission stability, and exhibiting low propagation loss. In complex urban environments, vertical polarization reduces the impact of obstacles such as buildings on the signal, improving communication reliability and providing strong anti-interference capabilities.

[0033] Dielectric substrate I1 serves as a supporting base, providing mechanical stability. Dielectric substrates II2 and III3, with their cross-shaped structures, integrate an elliptical monopole 4 at the center and symmetrically distribute zigzag parasitic structures on both sides, enabling multi-band and pattern reconfiguration functions. A DC bias line 11 is etched onto dielectric substrate I1, simplifying the bias network design and avoiding the impact of additional circuitry on antenna performance. Integration of the parasitic structures with the main radiator reduces antenna size, making it suitable for space-constrained mobile terminals or base station equipment. The compact structure lowers antenna height, improving device portability and installation flexibility.

[0034] Among them, PIN diodes are inexpensive and reliable, making them suitable for large-scale deployment. Reconfigurable operation requires only two PIN diodes and a switchable voltage, reducing system complexity and power consumption. The simplified structure reduces potential failure points and improves the long-term stability of the antenna. Dynamic reconfiguration reduces ineffective energy radiation, lowers system power consumption, and extends the battery life of mobile devices.

[0035] Specifically, by co-designing the parasitic structure along a tortuous line with the main radiator, broadband or multi-band operation can be achieved, adapting to different communication standards such as 2G / 3G / 4G / 5G / 6G. In base station applications, the beam direction and width can be adjusted in real time according to user mobility patterns (such as commuting during peak hours), balancing load capacity and improving network resource utilization. Pattern reconstruction can reduce signal reflection and scattering, mitigating the impact of multipath fading on communication quality. Polarization and pattern diversity enhance the reliability of communication between sensor nodes, meeting the needs of the Internet of Things (IoT).

[0036] In the above embodiments, the dielectric substrate I1 is further provided with a cross-shaped slot 101 at its center, and the dielectric substrate II2 and dielectric substrate III3 are fixed within the cross-shaped slot 101.

[0037] In the above embodiment, the cross-shaped slot 101 is further provided with a circular through hole 102 at its center, which provides the necessary installation space for subsequent welding of the coaxial feeder.

[0038] It should be noted that in the vertically polarized pattern reconfigurable antenna, by designing a circular through-hole 102 at the center of dielectric substrate I1 and fixing dielectric substrates II2 and III3 within the slot, the dual technical advantages of structural optimization and functional enhancement are achieved.

[0039] Specifically, a cross-shaped groove is formed by hollowing out the center of dielectric substrate I1, providing precise positioning for the embedding of dielectric substrates II2 and III3, avoiding the bulky size caused by traditional stacked designs. Dielectric substrates II2 and III3 are directly embedded in the groove, reducing interlayer gaps and lowering the overall antenna height, making it suitable for space-sensitive mobile terminals or miniaturized devices. The compact structure significantly reduces the antenna size, improving device portability and installation flexibility. Embedded fixation reduces the impact of vibration or shock on antenna performance, ensuring long-term reliability.

[0040] The circular through-hole 102, located at the center of the cross-shaped slot, provides a vertical soldering channel for coaxial feed lines (such as SMA connectors), ensuring precise alignment of the feed point with the center of the elliptical monopole 4. The circular through-hole 102 design allows for adjustment of impedance matching between the feed structure and the radiator, reducing reflection loss and improving antenna radiation efficiency. Clearly defined soldering space prevents feed line misalignment or short circuits, minimizing the impact of manufacturing errors on performance. The precise feed point design, combined with parasitic structures, enables broadband or multi-band operation, adapting to complex communication environments.

[0041] The cross-shaped slot 101 can form a microstrip line or slot line effect at its edge, coupling with the tortuous parasitic structures (Ⅰ21-Ⅳ32) on the dielectric substrates Ⅱ2 and Ⅲ3, enhancing the flexibility of pattern reconstruction. The circular via 102 acts as an electromagnetic barrier, reducing interference from the feed structure to the parasitic structure and ensuring the independence of pattern control. The coordinated design of the parasitic structure and the main radiator makes parameters such as beam pointing and sidelobe suppression easier to control, meeting the requirements of high-precision communication and improving pattern accuracy. The combination of switching diodes (D1-D4) and the slotted structure enables switching between multiple radiation modes, adapting to dynamic scenarios such as satellite tracking and mobile communication switching, providing multi-mode operation capabilities.

[0042] The cross-shaped slot 101 and the circular through-hole 102 can be completed in a single milling or laser processing, reducing process complexity. Dielectric substrates II2 and III3 can be pre-processed and then embedded into the slot, reducing assembly difficulty and improving production efficiency. Simplified processes reduce material waste and labor costs, making them suitable for mass production. Standardized structures reduce assembly errors and improve antenna performance consistency. The cross-shaped slot 101 can disperse the mechanical stress on dielectric substrate I1, reducing deformation caused by temperature changes or vibration. The circular through-hole 102 can serve as a heat dissipation channel, reducing the temperature rise of the dielectric material during high-frequency operation and ensuring long-term antenna stability. It adapts to harsh environments such as high temperature, high humidity, and vibration, extending antenna lifespan. Structural stability reduces the failure rate and lowers the need for subsequent maintenance.

[0043] Therefore, through the innovative design of the cross-shaped slot 101 and the circular through-hole 102, the antenna has achieved comprehensive optimization in terms of structure, performance, cost and adaptability, providing an efficient solution for demanding scenarios such as 5G / 6G communication, satellite navigation, and smart sensors.

[0044] In the above embodiments, further: elliptical monopoles I 41 are etched on the front side of the dielectric substrate II 2; elliptical monopoles II 42 are etched on the front side of the dielectric substrate III 3; an elongated rectangular slit 411 is formed at the upper end of the elliptical monopoles I 41; a short rectangular slit 421 is formed at the lower end of the elliptical monopoles II 42; the dielectric substrate II 2 and the dielectric substrate III 3 are connected and adapted through the elongated rectangular slit 411 and the short rectangular slit 421 to form the cross-shaped elliptical monopoles 4.

[0045] It should be noted that in the vertically polarized pattern reconfigurable antenna, elliptical monopoles I41 and II42 are etched on dielectric substrates II2 and III3 respectively, and a long rectangular slot 411 and a short rectangular slot 421 are designed for interlocking adaptation, forming a cross-shaped elliptical monopole 4. This achieves comprehensive optimization in performance, structure, cost, and adaptability, providing an efficient solution for high-bandwidth, multi-scenario communication. It features broadband and multi-band coverage, dynamic pattern reconfiguration, and strong beam scanning and sidelobe suppression capabilities. The interlocking adaptation design reduces size, improving portability and installation flexibility. Standardized processing reduces costs and improves yield and production efficiency.

[0046] Among them, the elliptical monopole 4 has a wider impedance bandwidth compared to traditional circular or rectangular monopoles. Its major-to-minor axis ratio can be adjusted to adjust the resonant frequency, covering a wider frequency band. Elliptical monopoles I41 and II42 on dielectric substrates II2 and III3 form a composite structure through a cross-shaped intersection, further extending the bandwidth. The two monopoles can operate in different frequency bands or generate multi-frequency resonant points through coupling. Located at the upper end of elliptical monopole I41, an additional resonant path can be introduced, reducing low-frequency impedance and enhancing bandwidth flatness. Located at the lower end of elliptical monopole II42, adjusting the slot length and width optimizes high-frequency matching and reduces resonant point offset. The synergistic design of the monopoles and slots allows the antenna to cover a wider frequency band. By controlling the parasitic structure through switching diodes, independent or joint operation of different frequency bands can be achieved, improving spectrum utilization.

[0047] The cross-shaped arrangement of elliptical monopoles I41 and II42 generates two orthogonal radiation modes, such as horizontal and vertical polarization components. These components can be dynamically combined to reconstruct the radiation pattern by controlling the parasitic structure using switching diodes. The long rectangular slit 411 and short rectangular slit 421 adjust the beamwidth, pointing, and sidelobe level of the radiation pattern by changing the surface current distribution. By controlling the switching diodes (D1-D4), beam scanning within a 360° range can be achieved, adapting to moving target tracking or interference suppression scenarios.

[0048] The insertion structure of the long rectangular slot 411 and the short rectangular slot 421 vertically intersects and fixes the two dielectric substrates (Ⅱ2 and Ⅲ3), reducing interlayer gaps and lowering the overall antenna height. Elliptical monopoles Ⅰ41 and Ⅱ42 can be pre-fabricated and then inserted through the slots, simplifying the assembly process and improving production efficiency. The compact structure significantly reduces the antenna size, making it suitable for space-constrained mobile terminals or miniaturized base stations. The insertion structure provides a rigid connection, reducing the impact of vibration or shock on antenna performance.

[0049] Simplified manufacturing processes and optimized materials make the antenna suitable for mass production, meeting the demands of low-cost communication equipment. Standardized processing reduces assembly errors and improves antenna performance consistency. The cross-shaped layout disperses mechanical stress on the dielectric substrate, reducing deformation caused by temperature changes or vibrations.

[0050] In the above embodiments, further: the elliptical monopole I 41 is provided with symmetrical zigzag parasitic structures I 21 and II 22 on its left and right sides; the elliptical monopole II 42 is provided with zigzag parasitic structures III 31 and IV 32 on its left and right sides.

[0051] It should be noted that the tortuous parasitic structures I21-IV32, as extensions of the radiator, can generate multiple resonant points with their tortuous shape, forming a composite radiation mode with the elliptical monopoles I41 and II42. By adjusting the length, width, and tortuosity of the parasitic structures, the surface current distribution can be precisely controlled, thereby changing the beamwidth, pointing direction, and sidelobe level of the radiation pattern. Symmetrical parasitic structures (such as I21 and II22, III31 and IV32) can generate a symmetrical radiation field, avoiding pattern shift. Furthermore, by independently controlling each group of parasitic structures, symmetrical scanning or asymmetrical control of the beam can be achieved.

[0052] The tortuous shape of the zigzag parasitic structure can introduce multiple resonant paths, which superimpose with the inherent resonant points of the elliptical monopole to form a broadband or multi-band response. For example, the parasitic structure can generate additional resonance in the high-frequency band (such as 5 GHz), extending the antenna bandwidth. The zigzag parasitic structure is directly etched on the edges of the dielectric substrates II2 and III3, requiring no additional space, and forms a compact layout with the elliptical monopoles I41 and II42. The parasitic structure and the main radiator are implemented on the same substrate, reducing interlayer interconnects and lowering assembly complexity.

[0053] In the above embodiments, further: PIN switching diodes D1 and D2 are respectively provided at the center connection of the zigzag parasitic structure I 21 and the zigzag parasitic structure II 22; the DC bias circuit I provided on the dielectric substrate II 2 conducts the PIN switching diodes D1 and D2; PIN switching diodes D3 and D4 are respectively provided at the center connection of the zigzag parasitic structure III 31 and the zigzag parasitic structure IV 32; the DC bias circuit II provided on the dielectric substrate III 3 conducts the PIN switching diodes D3 and D4.

[0054] It should be noted that by designing symmetrical tortuous parasitic structures on both sides of the elliptical monopoles I41 and II42, and integrating PIN switching diodes and DC bias circuits, dynamic control of radiation characteristics and functional expansion are achieved.

[0055] The PIN diodes (D1-D4) are controlled by DC bias circuits (I, II) to maintain their on / off state. When the diodes are on, the parasitic structure forms a short-circuit connection with the main radiator, altering the current path; when the diodes are off, the parasitic structure operates independently, generating a new resonant mode. By combining the switching states of different diodes (e.g., D1 / D2 on, D3 / D4 off), various radiation modes can be switched. For example: Omnidirectional mode: all diodes are off, the parasitic structure radiates independently, forming a wide beam coverage. Directional mode: a specific diode is on, the parasitic structure couples with the main radiator, generating a narrow beam pointing in a specific direction. Beam scanning mode: sequentially switching diode states allows the beam to scan within a 360° range, adapting to different communication scenarios. Nulling of the radiation pattern aligns with interference sources, improving the signal-to-noise ratio and enhancing anti-interference capabilities. The overall antenna size is significantly reduced, making it suitable for space-constrained platforms such as mobile terminals or drones. Integrated design reduces the number of solder joints and connectors, lowering the risk of poor contact.

[0056] Furthermore, the tortuous parasitic structure forms a rigid structure with the dielectric substrate, reducing deformation caused by vibration or impact. The tortuous shape of the parasitic structure increases the heat dissipation area, reducing the temperature rise of the dielectric material during high-frequency operation. The DC bias circuit employs a filtering design to suppress interference from RF signals on diode control. The PIN diodes and bias circuit components are selected to support operating temperatures from -40℃ to +85℃, adapting to harsh environments. This ensures long-term reliable operation of the antenna in high-temperature, high-humidity, and vibration environments. High reliability reduces the need for subsequent maintenance and extends product lifespan.

[0057] Therefore, through the innovative design of the tortuous parasitic structure and PIN switching diode, this invention achieves a comprehensive breakthrough in performance, structure, cost and adaptability of the antenna, providing an efficient solution for high-bandwidth, multi-scenario communication, and is especially suitable for high-end application fields such as smart terminals, vehicle communication, and satellite navigation.

[0058] In the above embodiments, further: a positive DC bias line I is provided on the center line of each of the tortuous line parasitic structures I 21 and II 22; a positive DC bias line II is provided on the center line of each of the tortuous line parasitic structures III 31 and IV 32; a rectangular ground plane 25 and two negative DC bias lines I are etched on the back side of the dielectric substrate II 2; two negative DC bias lines II are etched on the back side of the dielectric substrate III 3.

[0059] It should be noted that by integrating the positive DC bias line into the center line of the parasitic structure with a tortuous line, and designing a rectangular ground plane and a negative DC bias line on the back of the dielectric substrate, a deep integration of the DC bias circuit and the RF structure is achieved, resulting in high bias efficiency, compact structure, complete signal, and feasible manufacturing.

[0060] In this configuration, the positive DC bias line I / II extends along the centerline of the tortuous parasitic structure I21-Ⅳ32 and is directly connected to the anode of the PIN switching diodes (D1-D4). This arrangement allows the DC current to flow along the main current path of the parasitic structure, reducing parasitic resistance caused by uneven current distribution and thus lowering DC power consumption. The centerline layout minimizes the overlap between the bias line and the RF current path of the parasitic structure, significantly reducing the inductive coupling of the DC bias line to the RF signal.

[0061] The negative DC bias lines I / II are etched on the back side of the dielectric substrate II2 / III3, coplanar with the rectangular ground plane 25, reducing the complexity of the front layout and resulting in a more compact overall structure. The positive DC bias lines provide a stable DC operating point for the parasitic structure, preventing operating point drift caused by temperature changes or signal interference. The rectangular ground plane on the back provides a low-impedance path for the negative DC bias lines, reducing the ground loop impedance and minimizing signal coupling and noise interference.

[0062] The tortuous parasitic structure, combined with the positive DC bias line, allows for adjustment of the transmission line characteristic impedance. The layout of the negative DC bias line and the rectangular ground plane can influence the electromagnetic field distribution and optimize frequency selectivity.

[0063] The positive and negative DC bias lines are located on the front and back sides of the dielectric substrate, respectively, reducing the need for multilayer stacking and lowering manufacturing complexity and cost. The back-side etching process is compatible with the front-side parasitic structure processing, requiring no additional steps.

[0064] Among them, the tortuous parasitic structure can cover different frequency bands by adjusting its size, and the layout of the positive and negative bias lines supports flexible adjustment of operating voltage and current, adapting to various application scenarios. The independent bias line design of dielectric substrates II and III supports modular combination, which is convenient for expansion into an array structure and improves system performance.

[0065] In the above embodiments, the antenna further includes eight beams that are switched at 45° intervals under vertical polarization, and the antenna has an operating bandwidth covering 1.96 to 2.62 GHz, with a maximum gain of 5.5 dBi.

[0066] It's important to note that the multi-beam switching capability enhances spatial coverage and communication flexibility. The antenna switches between eight beams at 45° intervals, effectively dividing the 360° space into eight independent directions, with each beam able to independently adjust its radiation direction. This design allows for wider coverage and reduced blind spots in base station applications; in radar or satellite communications, rapid beam switching enables tracking of moving targets, improving system response speed. The beam switching function allows the antenna to dynamically adjust its radiation direction based on user location or signal strength, optimizing signal quality.

[0067] Among them, the 1.96–2.62 GHz frequency band is compatible: This band covers mainstream communication standards such as LTE, 5G Sub-6 GHz, and Wi-Fi 6E, enabling the antenna to be compatible with multiple wireless systems and reducing the number of devices and costs. The wideband design ensures good impedance matching within the frequency band and reduces return loss through optimized radiating element structure and matching network.

[0068] The 5.5dBi gain significantly improves signal transmission distance and interference resistance. In point-to-point communication, high-gain antennas reduce transmit power requirements and lower energy consumption; at the receiver, they improve the signal-to-noise ratio (SNR) and enhance communication quality. Combined with multi-beam switching functionality, the antenna can form a high-gain beam in a specific direction, further focusing energy.

[0069] Vertically polarized antennas, by matching the polarization of most mobile terminals (such as mobile phones), can reduce polarization mismatch losses and improve signal reception efficiency. Vertically polarized waves are less sensitive to ground reflections during propagation than horizontally polarized waves, reducing multipath interference. In complex electromagnetic environments (such as urban canyons), vertically polarized antennas can provide more stable communication links.

[0070] This design employs only vertical polarization, avoiding the complex feeding networks and isolation structures required for dual-polarized antennas, thus reducing manufacturing costs. Its wide bandwidth and multi-beam switching capabilities make it suitable for macro base stations, small base stations, and mobile terminals, supporting multi-band and multi-scenario communication. High gain and beamforming capabilities improve satellite communication link budget and enhance radar target detection capabilities. The vertical polarization and wide bandwidth design are compatible with Low Power Wide Area Network (LPWAN) and Vehicle-to-Everything (V2X) standards, supporting large-scale device connectivity.

[0071] In the above embodiments, the dielectric substrates I1, II2, and III3 of the antenna are made of dielectric materials with a dielectric constant of 4.4 ± 0.2 and a loss tangent of no more than 0.025, and the reconfigurable switching of the beam is achieved through specific thickness distribution.

[0072] It should be noted that precise control of the dielectric constant optimizes electromagnetic performance and beam characteristics. Low loss tangent improves antenna efficiency and gain. By adjusting the thickness distribution of dielectric substrates I, II, and III, the propagation phase of electromagnetic waves in each dielectric layer can be changed, thereby achieving reconfigurable beam direction switching. Thickness distribution design can simultaneously optimize beam characteristics in different frequency bands. Selecting dielectric materials with matched dielectric constants and loss tangents simplifies the integration process of multilayer dielectric substrates. No additional matching layers are needed between different dielectric layers, reducing manufacturing complexity and cost. Thickness distribution design requires high manufacturing precision, but using materials with stable dielectric constants reduces sensitivity to thickness errors. In 5G millimeter-wave and 6G terahertz communications, low-loss, high dielectric constant stability dielectric materials support miniaturization and efficient transmission of high-frequency antennas. Beam reconfigurability can meet the requirements of massive MIMO and beamforming, improving spectrum utilization. In satellite antennas, thickness distribution design enables on-orbit beam reconfiguration, adapting to communication needs at different orbital locations. Low-loss dielectrics reduce performance degradation in space radiation environments, extending satellite lifespan. Beam-reconfigurable antennas enable rapid target tracking in radar systems and dynamically adjust radiation direction to evade interference in electronic warfare. Dielectric constant stability ensures the reliability of radar systems in complex environments. Dielectric constant ε r While materials with a dielectric constant of 4.4 ± 0.2 and tanδ ≤ 0.025 are more expensive, their material usage can be reduced through thickness distribution design, balancing performance and cost. The selected dielectric material and thickness distribution scheme are compatible with existing PCB processes, supporting large-scale production.

[0073] In the above embodiments, the dielectric substrates I1, II2, and III3 are all made of FR4 material; the thickness of dielectric substrate I1 is 2 mm, and the thickness of dielectric substrates II2 and III3 is 1.6 mm.

[0074] It should be noted that FR4 is a glass fiber reinforced epoxy resin copper-clad laminate. Its raw material cost is low and the supply chain is mature, making it widely used in consumer electronics, communication equipment, and other fields. Compared to high-frequency materials, FR4 is only 1 / 3 to 1 / 5 the price, significantly reducing the overall cost of antennas. Dielectric substrate I uses a 2mm thickness, suitable for areas requiring higher mechanical strength or specific electromagnetic properties (such as radiating patch layers); while dielectric substrates II and III use a 1.6mm thickness, reducing material usage while meeting performance requirements. FR4 material is fully compatible with existing printed circuit board (PCB) processes, supporting automated production, multilayer lamination, chemical etching, and other standard processes. Compared to high-frequency materials, FR4 requires no special treatment, shortening the R&D cycle and reducing manufacturing risks. The thickness tolerance of FR4 material is typically ±10%, and thicknesses of 2mm and 1.6mm can meet most antenna design requirements. Multilayer FR4 structures can extend bandwidth through interlayer coupling. The 2mm thick dielectric substrate I provides higher bending strength, making it suitable as the main support structure for antennas. The 1.6mm thick dielectric substrates II and III are used for parasitic elements or grounding layers, maintaining structural stability while reducing weight. In phased array antennas, the combination of 2mm and 1.6mm thicknesses can create a phase gradient, supporting beam scanning functionality.

[0075] Therefore, this invention achieves an optimal balance between cost, process, performance and flexibility by combining FR4 material with thickness-differentiated design. It is particularly suitable for cost-sensitive communication scenarios that require large-scale deployment, such as 5G base stations and IoT devices, while meeting the requirements of multi-beam switching and high gain in the 1.96–2.62 GHz frequency band.

[0076] The technical effects of this invention will be further explained below based on simulation and test results: Simulation and testing conditions and content of this invention: This study utilized the ANSYS HFSS electromagnetic simulation platform to perform electromagnetic simulation and optimization design of the antenna, and systematically analyzed key parameters such as the antenna's impedance characteristics, radiation pattern, and gain. To verify the accuracy and reliability of the simulation results, a physical antenna was fabricated based on the simulation-optimized structural parameters. The antenna impedance characteristics were measured using a high-precision AV3672B vector network analyzer. Simultaneously, in a standard microwave anechoic chamber environment, the antenna's radiation pattern, gain, and other radiation characteristics were tested and evaluated using a far-field testing system.

[0077] Simulation and test results analysis of this invention: The designed pattern-reconfigurable antenna uses a cross-elliptical monopole antenna as the main radiating structure. Compared to a single elliptical monopole, the cross-elliptical monopole radiates energy more evenly in all directions to ensure the stability of the pattern in each state. It has two operating modes. In the first mode, three adjacent parasitic structures are in the "on" state, acting as reflectors; the third parasitic structure is in the "on" state, acting as a director; this operating mode is called the three-reflection mode. In the second mode, two adjacent parasitic structures are in the "on" state, acting as reflectors; the other two parasitic structures are in the "on" state, acting as directors; this operating mode is called the two-reflection mode. Due to the approximate symmetry of the antenna structure, the beam switching mechanism for states 1 / 3 / 5 / 7 is the same, all operating in the three-reflection mode. The beam switching mechanism for states 2 / 4 / 6 / 8 is also the same, all operating in the two-reflection mode. Table 1 below explains the operating principles of states 1 and 2: Table 1 Eight-beam diode corresponding states

[0078] By referring to the accompanying drawings in the instruction manual, we can see that: Figure 5 The simulated 3D radiation pattern of the antenna in all states at the center frequency is shown. This antenna can achieve eight beam switching steps in 45° increments by controlling the diode states on four zigzag parasitic structures, exhibiting good directional and directional capabilities.

[0079] Figure 6 shows the simulated and measured |S11| parameters of the antenna under all conditions. As shown in Figure 6(a), the simulated overlap bandwidth of the antenna under all conditions is 2.20–2.72 GHz; as shown in Figure 6(b), the measured overlap bandwidth of the antenna under all conditions is 1.96–2.62 GHz, with the measured relative bandwidth reaching 28.8%. The measured results show a frequency offset compared to the simulated results, mainly due to the actual dielectric constant of the substrate, coaxial cable feeding, processing errors, and assembly / welding tolerances.

[0080] Figure 7 This demonstrates the simulated and measured gain of the antenna. (By...) Figure 7 It can be seen that the simulated gain of the antenna is almost always above 4dBi within the operating bandwidth in all states. The gain in states 1 / 3 / 5 / 7 is lower than that in states 2 / 4 / 6 / 8. This is because states 2 / 4 / 6 / 8 are double-reflection modes, in which two parasitic structures act as directors, while states 1 / 3 / 5 / 7 are triple-reflection modes, in which only one parasitic structure acts as a director. Since the overall structure of the antenna is almost symmetrical, for ease of testing, only the measured gain results for the antenna operating in states 1 and 2 are given here. Figure 7It can be seen that the measured gain of the antenna in states 1 and 2 is slightly lower than the simulation results. This is mainly due to the losses of the dielectric substrate, coaxial cable and diode, as well as the assembly and welding tolerances.

[0081] Figure 8 The simulation efficiency of the antenna under all states is demonstrated. Figure 8 It can be seen that the simulated efficiency of the antenna is almost always above 65% within the operating bandwidth in all states. The efficiency of states 1 / 3 / 5 / 7 is lower than that of states 2 / 4 / 6 / 8. This is because states 2 / 4 / 6 / 8 belong to the double reflection mode, in which there are two parasitic structures acting as directors, while states 1 / 3 / 5 / 7 belong to the triple reflection mode, in which there is only one parasitic structure acting as a director.

[0082] Figure 9 shows the normalized simulated radiation pattern of the antenna in the H-plane at the center frequency. The results show that the antenna's 3dB beamwidth exhibits good stability and consistency under different operating states, with minimal differences in beam characteristics across states. In states 1 / 5, the cross-polarization level is close to -17 dB, while in states 2 / 3 / 4 / 6 / 7 / 8, the cross-polarization level is below -20 dB, indicating high polarization purity. Since the antenna structure at the center frequency is symmetrical between states 1, 2, 3, 4 and states 5, 6, 7, 8, only the radiation patterns for states 1, 2, 3, and 4 were tested here.

[0083] Figure 10 shows that the simulated and measured H-plane normalized radiation patterns of the antenna in states 1, 2, 3, and 4 are in good agreement with the simulation results. The minor differences are mainly caused by the parasitic effect of the DC bias line.

[0084] Figure 11 shows the normalized simulated E-plane radiation pattern of the antenna at the center frequency. Since the antenna operates in states 1, 2, 3, and 4 at the center frequency with structures 5, 6, 7, and 8, only the simulated E-plane radiation patterns for states 1, 2, 3, and 4 are given here. The results show that the cross-polarization voltage is below -20 dB, indicating high polarization purity. In summary, this invention relates to a vertically polarized eight-beam pattern reconfigurable antenna based on the Yagi antenna principle. This design achieves eight-beam switching while maintaining structural compactness, fully meeting the requirements for antenna miniaturization. The core design of the antenna uses a cross-elliptical monopole as the main radiating structure, and based on the Yagi antenna principle, it incorporates zigzag parasitic structures on its four sides. By controlling the switching state of the diodes, the parasitic structures can flexibly switch between being a guide or a reflector, thereby converting the omnidirectional radiation characteristics of the monopole into eight directional radiation modes. Simulation and test results show that this antenna can achieve stable switching of eight beams at 45° intervals under vertical polarization, with an operating bandwidth covering 1.96–2.62 GHz, and a maximum gain of 5.5 dBi within the operating bandwidth. Compared with existing vertically polarized pattern reconfigurable antennas, this design has significant advantages in terms of structural complexity, requires fewer PIN diodes, and simultaneously achieves excellent performance such as wide bandwidth, multi-beam switching, and no gain dead zone. These characteristics make it a promising candidate for applications in 5G / 6G mobile communications, smart antenna systems, and other scenarios.

[0085] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications and equivalent substitutions made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A vertically polarized pattern reconfigurable antenna, characterized in that: The device has a dielectric substrate I (1), which serves as a support base. A cross-shaped dielectric substrate II (2) and a dielectric substrate III (3) are fixedly positioned at the center of the upper surface of the substrate I (1). The cross-shaped dielectric substrate II (2) and dielectric substrate III (3) have cross-shaped elliptical monopoles (4) at their center. The dielectric substrate II (2) has a left-right symmetrical zigzag parasitic structure I (21) and a zigzag parasitic structure II (22). The dielectric substrate III (3) has a left-right symmetrical zigzag parasitic structure III. (31) and zigzag parasitic structure Ⅳ (32); the zigzag parasitic structure Ⅰ (21) has a PIN switching diode D1 at its center, the zigzag parasitic structure Ⅱ (22) has a PIN switching diode D2 at its center, the zigzag parasitic structure Ⅲ (31) has a PIN switching diode D3 at its center, and the zigzag parasitic structure Ⅳ (32) has a PIN switching diode D4 at its center; the dielectric substrate Ⅰ (1) is etched with a DC bias line (11); the dielectric substrate Ⅱ (2) is etched with a rectangular ground plane (25).

2. The vertically polarized pattern reconfigurable antenna according to claim 1, characterized in that: The dielectric substrate I (1) has a cross-shaped slot (101) at its center, and the dielectric substrate II (2) and dielectric substrate III (3) are fixed in the cross-shaped slot (101).

3. The vertically polarized pattern reconfigurable antenna according to claim 2, characterized in that: The cross-shaped slot (101) has a circular through hole (102) at its center.

4. The vertically polarized pattern reconfigurable antenna according to claim 1, characterized in that: The dielectric substrate II (2) has an elliptical monopole I (41) etched on the front side; the dielectric substrate III (3) has an elliptical monopole II (42) etched on the front side; the elliptical monopole I (41) has a long rectangular slot (411) at the upper end; the elliptical monopole II (42) has a short rectangular slot (421) at the lower end; the dielectric substrate II (2) and the dielectric substrate III (3) are connected and adapted through the long rectangular slot (411) and the short rectangular slot (421) to form the cross-shaped elliptical monopole (4).

5. The vertically polarized pattern reconfigurable antenna according to claim 4, characterized in that: The elliptical monopole I (41) has a left-right symmetrical zigzag parasitic structure I (21) and a zigzag parasitic structure II (22) on its left and right sides; the elliptical monopole II (42) has a zigzag parasitic structure III (31) and a zigzag parasitic structure IV (32) on its left and right sides.

6. The vertically polarized pattern reconfigurable antenna according to claim 5, characterized in that: The center connection of the parasitic structure I (21) and parasitic structure II (22) is provided with PIN switching diode D1 and PIN switching diode D2 respectively; the DC bias circuit I provided on the dielectric substrate II (2) conducts PIN switching diode D1 and PIN switching diode D2. The center connection of the parasitic structure Ⅲ (31) and the parasitic structure Ⅳ (32) is provided with PIN switching diode D3 and PIN switching diode D4 respectively; the DC bias circuit Ⅱ provided on the dielectric substrate Ⅲ (3) conducts PIN switching diode D3 and PIN switching diode D4.

7. The vertically polarized pattern reconfigurable antenna according to claim 6, characterized in that: The center lines of the parasitic structures I (21) and II (22) have a positive DC bias line I; the center lines of the parasitic structures III (31) and IV (32) have a positive DC bias line II; a rectangular ground plane (25) and two negative DC bias lines I are etched on the back side of the dielectric substrate II (2); two negative DC bias lines II are etched on the back side of the dielectric substrate III (3).

8. The vertically polarized pattern reconfigurable antenna according to any one of claims 1-7, characterized in that: The antenna achieves eight beam switching at 45° intervals under vertical polarization, and its operating bandwidth covers 1.96 to 2.62 GHz, with a maximum gain of 5.5 dBi.

9. The vertically polarized pattern reconfigurable antenna according to claim 8, characterized in that: The dielectric substrates I (1), II (2), and III (3) of the antenna are made of dielectric materials with a dielectric constant of 4.4 ± 0.2 and a loss tangent of no more than 0.025, and the reconfigurable switching of the beam is achieved through specific thickness distribution.

10. The vertically polarized pattern reconfigurable antenna according to claim 9, characterized in that: The dielectric substrates I (1), II (2), and III (3) are all made of FR4 material; the thickness of the dielectric substrate I (1) is 2 mm, and the thickness of the dielectric substrates II (2) and III (3) is 1.6 mm.

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