A 3D printed wideband high-gain fabry-perot resonator cavity base station antenna

Abstract

This application relates to the field of antenna technology, and more particularly to a 3D-printed broadband high-gain Fabry-Perot resonator base station antenna, comprising a metal ground plane; a bottom dielectric substrate disposed on the metal ground plane; a radiating patch disposed on the upper surface of the bottom dielectric substrate; an all-metal partially reflective surface disposed above the radiating patch, forming a Fabry-Perot resonator together with the metal ground plane; and a coaxial feed structure penetrating the metal ground plane and the bottom dielectric substrate, welded to the radiating patch. This application combines a slotted patch with an all-metal SLM PRS to construct a broadband high-gain FP resonator antenna, overcoming the shortcomings of traditional antennas such as narrow bandwidth, low gain, and high loss, achieving a bandwidth of 20.8% and a high gain of over 15dBi.

Description

Technical Field

[0001] This application relates to the field of antenna technology, and more specifically, to a 3D-printed broadband high-gain Fabry-Perot resonator base station antenna. Background Technology

[0002] With the continuous evolution from fifth-generation mobile communication (5G) to 5G-Advanced (5G-A), the accelerated deployment of sixth-generation mobile communication (6G) technology, and the rapid rise of new business forms such as mobile AI, multimodal interaction, industrial internet, vehicle-to-everything (V2X) communication, the new generation of mobile communication systems has placed unprecedentedly stringent requirements on ultra-high bandwidth, wide-area coverage, low latency, high reliability, high integration, and conformal adaptation.

[0003] Spectrum resources, as the core foundation of mobile communication development, directly determine network capacity, peak data rate, coverage quality, and system deployment costs. Against this backdrop, the 5.25-6.47 GHz band has become a globally recognized primary carrier band for 5G-A and a key candidate spectrum for 6G. It boasts significant advantages such as continuous high bandwidth, moderate propagation loss, balanced coverage, and high device maturity. It can support ultra-high bandwidth transmission on a single carrier, meeting core requirements such as 10 Gigabit speeds, high-capacity access, and wide-area coverage. Suitable for macro base stations, micro base stations, integrated small cells, and vehicle / airborne conformal communication terminals, it is the core operating frequency band for next-generation wireless communication and radio frequency sensing systems.

[0004] However, high-performance antennas targeting the 5.27-7.65 GHz frequency band must simultaneously meet multiple requirements, including wide bandwidth, high gain, low profile, structural stability, high power tolerance, and ease of integration. Traditional antenna technologies are no longer adequate for these needs. While microstrip patch antennas offer advantages such as low profile, conformal design, and low cost, they suffer from inherent low gain, limited bandwidth, and insufficient efficiency, failing to meet the demands for long-distance coverage and high-capacity transmission. Array antennas can improve gain through arraying, but their complex feeding networks, high losses, high profile, and strong inter-element coupling significantly increase the difficulty and cost of engineering implementation.

[0005] Fabry-Perot (FP) resonant cavity antennas have become the preferred solution for high-gain directional antennas due to their advantages such as low profile, no complex feed network, high aperture efficiency, and significant gain improvement. However, traditional FP antennas mostly adopt a dielectric substrate partial reflector (PRS) and fixed cavity high structure, which has defects such as narrow 3dB gain bandwidth, high dielectric loss, low power capacity, and poor environmental stability, making it difficult to cover the continuous large bandwidth requirements of 5.25-6.47GHz. At the same time, traditional PRS rely on etching, electroplating and other processes for fabrication, which have problems such as easy plating peeling, large assembly errors, and poor consistency. Under harsh conditions such as high temperature, vibration, and high power, the performance fluctuates significantly.

[0006] In summary, for the core 5G-A / 6G frequency band of 5.25-6.47GHz, existing antenna technologies suffer from prominent bottlenecks such as difficulty in balancing broadband and high gain, high loss, low power capacity, complex structure, low integration, and insufficient environmental robustness. There is an urgent need for a new type of FP cavity antenna that combines ultra-wideband, high gain, low loss, high power tolerance, simple structure, and easy integration to break through the limitations of traditional technologies and meet the needs of large-scale deployment and high-performance applications of next-generation mobile communications, broadband wireless transmission, radar sensing, and integrated terminals in the 5.25-6.47GHz frequency band. Summary of the Invention

[0007] In view of this, this application provides a 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna, which enables the antenna to have broadband high gain and solves the technical problems of insufficient bandwidth, low gain and complex structure of traditional base station antennas.

[0008] The technical solution provided in this application is as follows: A 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna, comprising: Metal flooring; A bottom dielectric substrate is disposed on the metal floor; A radiating patch is disposed on the upper surface of the underlying dielectric substrate; A fully metallic partially reflective surface is disposed above the radiating patch and together with the metal floor forms a Fabry-Perot resonant cavity; A coaxial power supply structure extends through the metal floor and the underlying dielectric substrate, and is soldered to the radiating patch.

[0009] In one possible implementation, the radiating patch is disposed at the center of the upper surface of the underlying dielectric substrate, and the geometric center of the radiating patch coincides with the geometric center of the underlying dielectric substrate.

[0010] In one possible implementation, the radiating patch has a slotted structure.

[0011] In one possible implementation, the groove structure is a U-shaped groove structure, located at opposite edges on one side of the radiating patch; the U-shaped groove structure includes two symmetrically arranged longitudinal grooves and a transverse groove located at one edge of the radiating patch and connecting the two longitudinal grooves.

[0012] In one possible implementation, the all-metal part of the reflective surface is composed of multiple all-metal Jerusalem cross grooves, and the multiple all-metal Jerusalem cross groove units are periodically arranged at equal intervals along the transverse and longitudinal directions.

[0013] In one possible implementation, the all-metal Jerusalem cross groove has a centrally symmetrical structure, including a central cross groove body that is orthogonally connected to each other, and four end groove bodies that are respectively connected to the outer ends of each arm of the central cross groove body.

[0014] In one possible implementation, the all-metal partially reflective surface is fabricated using a selective laser melting process and is used as the upper structure of the Fabry-Perot resonator.

[0015] In one possible implementation, the coaxial power supply structure is a coaxial SMA connector.

[0016] In one possible implementation, the impedance bandwidth of the broadband high-gain Fabry-Perot resonator base station antenna is 5.25 GHz to 6.47 GHz.

[0017] Compared with the prior art, the technical solution provided in this application has the following beneficial effects: This technical solution expands the impedance matching bandwidth by creating a slotted radiating patch. A fully metallic Jerusalem cross-shaped groove, integrally formed using selective laser melting, constitutes the all-metal partial reflective surface. This all-metal partial reflective surface, together with the metal ground plane, constructs a Fabry-Perot resonant cavity. The multiple reflections and transmissions of electromagnetic waves within the resonant cavity, along with the coherent superposition effect, significantly enhance the antenna's radiation gain and directional radiation characteristics.

[0018] Meanwhile, by precisely controlling the amplitude and phase of reflection from the partial reflective surface, the effectiveness and gain flatness of in-phase superposition across a wide frequency band are ensured, effectively overcoming the technical limitations of traditional Fabry-Perot antennas, such as narrow bandwidth and large gain fluctuations. The fully metallized partial reflective surface avoids the defects of traditional dielectric substrate partial reflective surfaces, such as high dielectric loss, easy coating peeling, and poor environmental stability. It has significant advantages such as low transmission loss, high power tolerance, strong structural robustness, and good adaptability to operating conditions. Moreover, the overall antenna structure is simple, easy to assemble, and easy to ensure consistency. It can be widely adapted to various application scenarios such as 5G / 6G mid-band communication, wireless LAN, industrial radar, and ultra-wideband positioning systems, and has good engineering practical value and market application prospects. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna provided in Embodiment 1 of this application.

[0020] Figure 2 A schematic diagram of the reflection amplitude and reflection phase curves of the PRS provided in Example 2 of the application.

[0021] Figure 3 This is a schematic diagram of the reflection and radiation amplitude curves of the PRS provided in Example 2 of the application.

[0022] Figure 4 This is a schematic diagram of the reflection and radiation phase curves of the PRS provided in Example 2 of the application.

[0023] Figure 5 A schematic diagram comparing the S11 curves of the 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna and the source antenna provided in Embodiment 2 of the application.

[0024] Figure 6 This is a schematic diagram comparing the gain of the 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna with the gain of the source antenna, as provided in Embodiment 2 of the application.

[0025] Figure 7 This is a schematic diagram of the combined S11 and gain characteristic curves of the 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna provided in Embodiment 2 of the application.

[0026] Figure 8 The radiation pattern at 5.28 GHz of the 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna provided in Embodiment 2 of the application.

[0027] Figure 9 The radiation pattern at 5.5 GHz of the 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna provided in Embodiment 2 of the application.

[0028] Figure 10 The radiation pattern at 5.85 GHz of the 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna provided in Embodiment 2 of the application.

[0029] Explanation of reference numerals in the attached drawings: 1. Metal floor; 2. Bottom dielectric substrate; 3. Radiation patch; 4. All-metal partial reflective surface; 5. Coaxial feeding structure; 30. Slot structure; 40. All-metal Jerusalem cross slot; 401. Central cross slot; 402. End slot. Detailed Implementation

[0030] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0031] Example 1 See Figure 1This is a schematic diagram of the structure of a 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna provided in Embodiment 1 of this application. Figure 1 As shown, the antenna includes a metal ground plane 1, a bottom dielectric substrate 2, a radiating patch 3, an all-metal partial reflective surface 4, and a coaxial feed structure 5.

[0032] Specifically, the aforementioned bottom dielectric substrate 2 is disposed on the aforementioned metal ground plane 1. The aforementioned radiating patch 3 is disposed on the upper surface of the aforementioned bottom dielectric substrate 2. The aforementioned all-metal partially reflective surface 4 is disposed above the aforementioned radiating patch 3, and together with the aforementioned metal ground plane 1, forms a Fabry-Perot resonant cavity. The aforementioned coaxial feed structure 5 penetrates the aforementioned metal ground plane 1 and bottom dielectric substrate 2, and is soldered to the aforementioned radiating patch 3.

[0033] In some embodiments, the radiating patch 3 is located in the middle of the upper surface of the underlying dielectric substrate 2. The center of the radiating patch 3 is the center of the bottom dielectric substrate, that is, the geometric center of the radiating patch 3 coincides with the geometric center of the underlying dielectric substrate 2. The overall dimensions of the radiating patch 3 are obtained through calculation. Considering the bandwidth, it is slotted, which relatively improves the bandwidth.

[0034] Furthermore, the aforementioned radiating patch 3 also has a slot structure 30 for expanding the impedance bandwidth of the antenna. For example... Figure 1 As shown, the aforementioned groove structure 30 is a U-shaped groove, located at the opposite edge of one side of the radiating patch 3. The aforementioned U-shaped groove includes two symmetrically arranged longitudinal grooves and a transverse groove located at one edge of the radiating patch 3 and connecting the two aforementioned longitudinal grooves.

[0035] The aforementioned all-metal reflective surface 4 is arranged in an array, consisting of 40 all-metal Jerusalem cross-shaped groove elements. Multiple all-metal Jerusalem cross-shaped groove elements 40 are periodically arranged at equal intervals along the transverse and longitudinal directions. Optionally, such as... Figure 1 As shown, the aforementioned all-metal part of the reflective surface 4 can be arranged in a 5×5 array.

[0036] like Figure 1 As shown, the all-metal Jerusalem cross groove 40 has a centrally symmetrical structure, including a central cross groove 401 that is orthogonally connected to each other, and four end grooves 402 that are respectively connected to the outer ends of each arm of the central cross groove 401.

[0037] As an improvement, to overcome the narrow-band limitation of traditional FP antennas, the all-metal partial reflective surface 4 described in this application is integrally formed using selective laser melting (SLM) technology. This ensures stable reflection amplitude and linear phase change within the 5.25GHz-6.47GHz frequency band, guaranteeing continuous in-phase superposition and flat gain across a wide bandwidth. Ultimately, the antenna achieves low return loss, high gain, and stable directional radiation within the 5.25GHz-6.47GHz range. It retains the advantages of FP antennas without complex feed networks while solving the problems of narrow bandwidth and large gain fluctuations in traditional planar FP antennas, thus meeting the engineering requirements of large bandwidth and high gain in the corresponding frequency band.

[0038] This application employs an all-metal partial reflective surface manufactured using selective laser melting to form the upper structure of the resonant cavity. Precise amplitude and phase characteristics are achieved through a Floquet port. During operation, the aforementioned coaxial feed structure 5 excites the aforementioned radiating patch 3, and electromagnetic waves form a resonant cavity between the metal floor 1 and the all-metal partial reflective surface 4. Coherent superposition is achieved through multiple reflections and transmissions, significantly improving radiation gain and directivity.

[0039] In summary, compared with the prior art, the technical solution provided in Embodiment 1 of this application has the following beneficial effects: Compared to existing technologies, this application introduces a fully metallic partial reflective surface manufactured by selective laser melting (SLM), a Floquet partial reflective structure, and a broadband resonant cavity matching design, which significantly improves gain and broadens the operating bandwidth, achieving stable radiation characteristics. The introduction of the fully metallic partial reflective surface manufactured by selective laser melting (SLM) enables all-metal integration, low loss, and high efficiency. At the same time, the all-metal structure contains no polymer materials, is resistant to high temperatures and high power, and is suitable for radar and high-power microwave systems, with no risk of thermal deformation or dielectric breakdown.

[0040] The 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna of this application adopts source antenna, partial reflector, metal ground plane 1 and Floquet port analysis to achieve broadband high-gain radiation, which can be adapted to multiple application scenarios such as Wi-Fi 5 / 6 / 6E wireless LAN, 5G / 6G mid-band communication, 5.8GHz industrial radar, UWB positioning system and radio frequency testing.

[0041] This antenna is integrally formed using selective laser melting (SLM) technology, featuring high power capacity, low loss, and strong structural robustness, making it particularly suitable for high-reliability, high-power-density communication and sensing equipment. This application utilizes SLM direct forming of an all-metal Jerusalem cross-groove 40PRS antenna, exhibiting strong structural robustness and possessing significant engineering application value and market potential.

[0042] Example 2 In Embodiment 2 of this application, a PCB board (Arlon AD255A) is used as the dielectric substrate, and a coaxial power supply SMA connector is soldered on it. The metal ground plane 1 is 125mm long and 125mm wide.

[0043] The bottom dielectric substrate 2 is 125mm long, 125mm wide, and 2.8mm high. The radiating patch 3 is 20.1mm long and 14.3mm wide, with a 9.7mm long and 2.5mm wide groove cut off from its edge, and two symmetrical grooves 9.2mm long and 0.9mm wide. The PRS unit is 25mm long, 25mm wide, and 2mm high. The Jerusalem cross slot 40 has a symmetrical structure, with the central cross slot being 16mm long, 2mm wide, and 2mm high, and the other four slots being 10mm long, 2mm wide, and 2mm high. Its resonant cavity height is 31.5mm.

[0044] The aforementioned 3D-printed broadband high-gain Fabry-Perot (FP) antenna operates based on the principle of cavity multi-wave interference enhanced radiation, achieving broadband, high-gain, and stable radiation within the 5.25GHz-6.47GHz range. The antenna consists of a source antenna, a metal ground plane, and an all-metal partial reflective surface (PRS), and is analyzed using cavity modulation and Floquet port analysis.

[0045] The source antenna acts as a radiating excitation, radiating electromagnetic waves into the cavity. A portion of the electromagnetic waves radiates directly through the PRS and outwards, while the other portion is reflected multiple times by the floor and the PRS, forming a coherent standing wave resonance within the cavity. By adjusting the PRS reflection phase and matching the cavity height and curvature, the multiple reflected waves and the directly transmitted waves within the cavity are superimposed in phase, significantly improving the aperture radiation efficiency and far-field gain, forming a highly directional pencil beam.

[0046] By performing HFSS simulation on the designed structure, and utilizing software simulation and optimization of various antenna performance indicators, the antenna's S11, gain, and radiation pattern are derived from the final results. Figures 2-10 As shown in the image.

[0047] Specifically, this embodiment of a 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna consists of a ground plane, a radiating patch, a bottom dielectric substrate, a coaxial feed, and a PRS. First, the PRS unit is analyzed using a Floquet port; its amplitude and phase modulation are as follows... Figure 3 and Figure 4 As shown. At 4.7GHz, its reflection amplitude is relatively ideal, and its transmission amplitude is close to 1, making it easy to achieve high gain. The reflection coefficient S11 at its antenna input port is less than -10dB at this point. Its reflection phase is negative in the 5.25GHz-6.47GHz range, which is also a frequency band that maintains high gain and ideal radiation effect.

[0048] To visually demonstrate the improved impedance matching performance of this application compared to the source antenna, the reflection coefficient S11 of the source antenna and the FP resonant cavity antenna of this application are compared. Figure 5 As shown, the horizontal axis represents the operating frequency in GHz, ranging from 5.2 GHz to 6.4 GHz. The vertical axis represents the return loss S11 in dB. The source antenna achieves impedance matching better than -10 dB only in the 5.4-6.2 GHz band, while the FP resonant cavity antenna operates in the 5.25-6.4 GHz band.

[0049] like Figure 6 The figure shows a gain comparison curve between the source antenna and the FP resonant cavity antenna of this application. The horizontal axis represents the operating frequency of 5.2 GHz to 6.4 GHz, and the vertical axis represents the antenna radiation gain (dBi). The black solid line corresponds to the source antenna without the PRS metasurface, and the source antenna's S11 (≤ The impedance bandwidth is 5.36 GHz-6.32 GHz (10 dB). Its gain remains stable in the range of 7~8.2 dBi throughout, with limited gain improvement.

[0050] After adding to the PRS array, S11 (≤ The impedance bandwidth (10dB) is 5.25GHz-6.47GHz, with a relative bandwidth of 20.8%, and its in-band gain can reach nearly 16dBi. For example... Figure 6 As shown in the figure, the cyan dashed line represents the FP antenna of this application. Its gain initially increases and then decreases, peaking at approximately 15.7 dBi near 5.5 GHz, representing a gain improvement of over 7 dB compared to the source antenna. Within the 5.2–6.2 GHz frequency band, the FP antenna gain is significantly higher than the source antenna, with the gain only rapidly decreasing and falling below that of the source antenna above 6.2 GHz. This figure visually demonstrates that by constructing an FP resonant cavity, this application can significantly improve the antenna radiation gain in the main operating frequency band, effectively enhancing the directional radiation capability of electromagnetic waves.

[0051] Figure 7 The figure shows the combined S11 and gain characteristic curves of the FP resonant cavity antenna of this application. The horizontal axis represents the operating frequency of 5.2~6.4GHz, the left vertical axis represents the return loss S11 (dB), and the right vertical axis represents the radiation gain (dBi). The downward arrow corresponds to the return loss curve, where the antenna achieves a depth matching of -40dB at 5.65GHz, and the S11 is below -10dB in the 5.25~6.4GHz range. The gray filled area represents the effective operating bandwidth. The right arrow corresponds to the gain curve, where the antenna's peak gain exceeds 15dBi, and the gain is stably greater than 6dBi within the fully matched bandwidth. This figure visually demonstrates that the FP resonant cavity structure of this application can simultaneously achieve wideband impedance matching and stable high-gain radiation.

[0052] Its E-plane and H-plane radiation patterns at 5.28 GHz, 5.5 GHz, and 5.85 GHz are as follows: Figure 8 - Figure 10 As shown, its radiation is relatively concentrated at 0°. In summary, the all-metal partial reflective surface manufactured by selective laser melting (SLM) in this application has strong structural robustness, and the addition of PRS can achieve high gain.

[0053] This second embodiment successfully solves the technical challenges of narrow bandwidth and large gain fluctuations in traditional Fabry-Perot antennas by combining a microstrip patch antenna with a broadband partial reflective surface (PRS). Because microstrip patch antennas have advantages such as low profile, ease of fabrication, and simple structure, this embodiment selects a microstrip patch antenna as the feed source for the Fabry-Perot resonant cavity antenna.

[0054] Within the 5.25GHz-6.47GHz frequency band, a comprehensive performance improvement in wide impedance bandwidth, high gain, and directional radiation was achieved. The proposed 3D-printed broadband high-gain FP resonant cavity antenna features a simple structure, convenient fabrication, and user-friendly installation. Furthermore, it is integrally formed using selective laser melting (SLM) technology, exhibiting high power capacity, low loss, and strong structural robustness. It is particularly suitable for high-reliability, high-power-density communication and sensing equipment, demonstrating significant engineering practical value and broad application prospects.

[0055] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna, characterized in that, include: Metal floor (1); The bottom dielectric substrate (2) is disposed on the metal floor (1); A radiating patch (3) is disposed on the upper surface of the underlying dielectric substrate (2); A fully metallic partially reflective surface (4) is disposed above the radiating patch (3) and together with the metal floor (1) forms a Fabry-Perot resonant cavity; A coaxial power supply structure (5) penetrates the metal floor (1) and the underlying dielectric substrate (2) and is soldered to the radiating patch (3).

2. The 3D-printed base station antenna with a high-gain Fabry-Perot resonator according to claim 1, characterized in that, The radiating patch (3) is disposed at the center of the upper surface of the bottom dielectric substrate (2), and the geometric center of the radiating patch (3) coincides with the geometric center of the bottom dielectric substrate (2).

3. The 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna according to claim 1, characterized in that, The radiation patch (3) has a groove structure (30).

4. The 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna according to claim 3, characterized in that, The groove structure (30) is a U-shaped groove structure, located at the opposite edge on one side of the radiating patch (3); the U-shaped groove structure includes two longitudinal grooves arranged symmetrically and a transverse groove located at one edge of the radiating patch (3) and connecting the two longitudinal grooves.

5. A 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna according to claim 1, characterized in that, The all-metal part of the reflective surface (4) is composed of multiple all-metal Jerusalem cross grooves (40), and the multiple all-metal Jerusalem cross groove (40) units are arranged periodically at equal intervals in the transverse and longitudinal directions.

6. A 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna according to claim 5, characterized in that, The all-metal Jerusalem cross groove (40) has a centrally symmetrical structure, including a central cross groove (401) that is orthogonally connected to each other, and four end grooves (402) that are respectively connected to the outer ends of each arm of the central cross groove (401).

7. A 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna according to claim 1, characterized in that, The all-metal part of the reflective surface (4) is made by selective laser melting and is used as the upper structure of the Fabry-Perot resonator.

8. A 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna according to claim 1, characterized in that, The coaxial power supply structure (5) is a coaxial SMA connector.

9. A 3D-printed broadband high-gain Fabry-Perot resonant cavity base station antenna according to claim 1, characterized in that, The impedance bandwidth of the broadband high-gain Fabry-Perot resonant cavity base station antenna is 5.25GHz-6.47GHz.

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