Ku / K dual-band common-caliber antenna with coplanar structure

Abstract

The invention discloses a Ku / K dual-band common-caliber antenna with a coplanar structure, which comprises a first dielectric plate, a second dielectric plate, a metal layer and a third dielectric plate which are sequentially arranged from top to bottom and are connected in a prepreg pressing manner, a first radiation patch, a second radiation patch and a first grounding plate are arranged on the front surface of the first dielectric plate; an L-shaped probe is arranged on the front surface of the second dielectric plate; an H-shaped gap is formed in the metal layer; and a first feed structure, a second feed structure and a second grounding plate are arranged on the reverse side of the third dielectric plate. The antenna provided by the invention is small in occupied space, high in isolation degree and high in antenna gain, and the aperture utilization rate is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and specifically to a coplanar Ku / K dual-band common-aperture antenna. Background Technology

[0002] With the rapid development of satellite communication, radar detection, and 5G technology, multi-band, highly integrated, and multifunctional antenna systems have become a research hotspot. Ku-band and K-band antennas, with their low interference and strong penetration characteristics, occupy an important position in satellite communication and millimeter-wave radar. However, traditional multi-band antennas often face problems such as large size, low isolation, and limited scanning range. Therefore, the emergence of common-aperture antenna technology provides a new approach to solving these problems. By integrating antennas of different frequency bands, polarizations, or functions into the same radiating aperture, it can not only significantly improve space utilization but also reduce electromagnetic interference to a certain extent, making it possible to achieve miniaturization and multifunctionality of antenna systems.

[0003] Jae-Hyun Kim et al. proposed a novel shared-aperture S / X dual broadband microstrip antenna design (Kim J, Hong SK, Kim BA shared-aperture S / X dual broadband microstrip antenna with one perforated patch[J]. Microwave and Optical Technology Letters, 2020, 62(1): 507-513). This design utilizes three layers of Taconic TLY-5 dielectric without air gaps. The S-band achieves broadband by combining a perforated patch with a three-segment feed line and aperture resonance. The X-band extends bandwidth using a stacked patch and aperture-coupled feed structure, but this design suffers from low isolation and is prone to coupling. Yin designed a Ku antenna for horizontal polarization and a Ka antenna for vertical polarization (Yin Yiting. Ku / Ka Dual-Band Shared-Aperture Phased Array Antenna Design[D]. University of Electronic Science and Technology of China, 2022). The Ku antenna effectively extends the antenna bandwidth through slot coupling combined with an air cavity, but it occupies a large space. Ma proposed a tri-band quad-feed MIMOTB antenna (Manish Sharma. A Tri-Band Quad Feed MIMOTB Antenna with Two-Narrow in Ku-KBands and n259 / n260 5G-mmWave FR2-Bands[C].IEEE Microwaves, 2023, 1-6), featuring dual narrow Ku-K bands and n259 / n260 5G-mmWave FR2 bands. The patch consists of rings embedded within a slotted hexagonal geometry, but has low gain. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a coplanar Ku / K dual-band common aperture antenna, which solves the problems of most current antennas occupying a large space, being unable to change the filtering characteristics according to the environment, having low gain, and slow beam scanning speed, and has the characteristics of high gain and strong directivity.

[0005] To solve the above technical problems, the present invention adopts the following technical solution:

[0006] A coplanar Ku / K dual-band common-aperture antenna includes:

[0007] The first dielectric plate, the second dielectric plate, the metal layer, and the third dielectric plate, arranged sequentially from top to bottom, are connected by a prepreg pressing method.

[0008] The front side of the first dielectric substrate is provided with a first radiating patch, a second radiating patch, and a first ground plane.

[0009] An L-shaped probe is placed on the front side of the second dielectric substrate.

[0010] The interior of the metal layer has an H-shaped slit.

[0011] The reverse side of the third dielectric substrate is provided with a first power supply structure, a second power supply structure, and a second grounding plate.

[0012] Furthermore, the microstrip rectangle is chamfered to obtain the first radiating patch.

[0013] The first radiating patches are arranged periodically on the first dielectric substrate, with a spacing of 9.1 mm between adjacent first radiating patches.

[0014] The outer chamfer and the inner groove of the second radiating patch form an L-shaped gap, which is symmetrically distributed with the second radiating patch as the center.

[0015] The second radiating patches are arranged periodically on the first dielectric substrate, with a spacing of 16.4 mm between adjacent second radiating patches.

[0016] The first grounding plate is located at both ends of the first medium plate.

[0017] Furthermore, the L-shaped probe is connected to the first feeding structure, and the L-shaped probe is fed to the second radiating patch using a non-contact structure.

[0018] Furthermore, the H-shaped slit and the second feeding structure use a non-contact structure to feed the first radiating patch.

[0019] Furthermore, both the first and second power supply structures are T-power dividers. The first power supply structure is symmetrically distributed with the center of the third dielectric plate as the center, and the second power supply structure is a 1-to-4 structure arranged in a 4×4 pattern to form a 1-to-16 structure.

[0020] The second grounding plate is located at both ends of the third medium plate.

[0021] Furthermore, the first dielectric substrate is made of F4b material with a dielectric constant of 2.2 and a thickness of 0.508 mm.

[0022] Furthermore, the second dielectric substrate is an adhesive layer made of FR-25 material with a dielectric constant of 2.45 and a thickness of 0.26 mm.

[0023] Furthermore, the third dielectric substrate is made of F4b material with a dielectric constant of 2.2 and a thickness of 0.254 mm.

[0024] Compared with the prior art, the present invention, employing the above technical solution, has the following technical effects:

[0025] The antenna proposed in this invention occupies a small space, has high isolation, and will not cause electromagnetic interference with other antennas. Furthermore, the antenna proposed in this invention has high gain, effectively improving aperture utilization, and is equipped with a feed network for the corresponding frequency band. Attached Figure Description

[0026] Figure 1 This is an overall structural diagram of the antenna of the present invention.

[0027] Figure 2 This is a top view of the antenna of the present invention.

[0028] Figure 3 This is a side view of the antenna of the present invention.

[0029] Figure 4 This is a structural diagram of the first dielectric plate of the present invention.

[0030] Figure 5 This is a structural diagram of the second dielectric plate of the present invention.

[0031] Figure 6 This is a diagram of the metal layer structure of the present invention.

[0032] Figure 7 This is a structural diagram of the third dielectric plate of the present invention.

[0033] Figure 8 This is a physical diagram of the antenna and a diagram of the far-field test environment of the present invention.

[0034] Figure 9 S is an embodiment of the present invention. 11 A comparison chart of the curve results.

[0035] Figure 10 This is a comparison chart of the isolation results between the Ku band and the K band in an embodiment of the present invention.

[0036] Figure 11 This is a comparison diagram of the results of Ku-band gain direction in an embodiment of the present invention.

[0037] Figure 12 This is a comparison diagram of the K-band polarization direction results in an embodiment of the present invention.

[0038] Figure 13 This is a comparison chart of the K-band axial bandwidth results in an embodiment of the present invention.

[0039] Reference numerals: A1-First dielectric substrate, B1-Second dielectric substrate, C1-Metal layer, D1-Third dielectric substrate, A2-First radiating patch, A3-Second radiating patch, B2-L-shaped probe, C2-H-shaped slot, D2-First feeding structure, D3-Second feeding structure. Detailed Implementation

[0040] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0041] To achieve the above objectives, this invention proposes a coplanar Ku / K dual-band common-aperture antenna, such as... Figure 1 , Figure 2 , Figure 3 As shown, it includes:

[0042] The first dielectric plate A1, the second dielectric plate B1, the metal layer C1 and the third dielectric plate D1, arranged sequentially from top to bottom, are connected by a prepreg pressing method.

[0043] The front side of the first dielectric plate A1 is provided with a first radiating patch A2, a second radiating patch A3 and a first ground plane.

[0044] An L-shaped probe B2 is placed on the front side of the second dielectric substrate B1;

[0045] The interior of the metal layer C1 has an H-shaped slit C2;

[0046] The reverse side of the third dielectric substrate D1 is provided with a first power supply structure D2, a second power supply structure D3, and a second grounding plate.

[0047] like Figure 4 As shown, the first dielectric substrate A1 is made of F4b material with a dielectric constant of 2.2 and a thickness of 0.508 mm.

[0048] The microstrip rectangle is chamfered to obtain the first radiating patch A2; the first radiating patches A2 are periodically arranged on the first dielectric substrate A1, and the spacing between adjacent first radiating patches A2 is 9.1 mm.

[0049] The external chamfer and the internal slot of the second radiating patch A3 form an L-shaped gap, which is symmetrically distributed with the second radiating patch A3 as the center; the second radiating patches A3 are periodically arranged on the first dielectric plate A1, and the spacing between adjacent second radiating patches A3 is 16.4 mm.

[0050] The first ground plane is located at both ends of the first dielectric plate A1. The first ground plane is GND in the figure and is made of metal.

[0051] The dimensions of the radiation patch are L0 = 52mm, L1 = 2.9mm, L2 = 0.6mm, L3 = 1.6mm, W1 = 7.5mm, W2 = 2mm, W3 = 0.4mm, and W4 = 1.1mm.

[0052] The dimensions of the first mounting plate are L4 = 5.6 mm and W5 = 25 mm.

[0053] like Figure 5 As shown, the second dielectric substrate B1 is an adhesive layer made of FR-25 material with a dielectric constant of 2.45. It has a length L0 of 52 mm and a thickness of 0.26 mm, and can accommodate the feed line and ground plane. The inner conductor of the coaxial line passes through the ground plane and connects to the feed line of the intermediate layer, forming an L-shaped probe B2. Using the L-shaped probe B2 reduces cross-polarization and improves polarization purity.

[0054] L-shaped probe B2 is connected to the first feeding structure D2, and L-shaped probe B2 uses a non-contact structure to feed the second radiating patch A3.

[0055] The dimensions of the L-shaped probe B2 are L1 = 0.8 mm, L2 = 1.2 mm, L3 = 4.8 mm, W1 = 0.8 mm, and W2 = 1.4 mm.

[0056] like Figure 6 As shown, to achieve fixed right-hand circular polarization within the operating frequency band, and considering the ease of subsequent array assembly, a simple microstrip rectangular chamfered patch is chosen for the K-band design. Coaxial feeding is used to power the patch, introducing a rectangular slit. Slit coupling is employed to further improve the impedance bandwidth. Vertical slits are added at both ends of the central slit, forming an H-shaped slit-coupled feeding system.

[0057] The H-shaped slit C2 and the second power supply structure D3 use a non-contact structure to power the first radiating patch A2.

[0058] The length of the metal layer C1 is 52 mm.

[0059] The dimensions of the H-shaped slit C2 are L1 = 1.4 mm, W1 = 1.2 mm, and W2 = 0.2 mm.

[0060] like Figure 7 As shown, the third dielectric substrate D1 is made of F4b material with a dielectric constant of 2.2, with a length of L0 = 52 mm and a thickness of 0.254 mm.

[0061] Both the first power supply structure D2 and the second power supply structure D3 are T-power dividers. The first power supply structure D2 is symmetrically distributed with the center of the third dielectric plate D1 as the center. The second power supply structure D3 is a 1-to-4 structure arranged in a 4×4 pattern to form a 1-to-16 structure.

[0062] The second ground plane is set at both ends of the third dielectric board D1. The second ground plane is GND in the figure and is made of metal.

[0063] The dimensions of the power supply structure are: L1 = 6mm, L2 = 12.25mm, L3 = 6.875mm, L4 = 4.1mm, L5 = 3.05mm, W1 = 16.67mm, W2 = 8.5mm, W3 = 2.3mm, W4 = 1.27mm, W5 = 2.15mm, W6 = 7.2mm, W7 = 0.75mm, and W8 = 0.7mm.

[0064] The dimensions of the second mounting plate are L6 = 5.6 mm; W9 = 25 mm.

[0065] The antenna proposed in this invention was simulated and fabricated for testing. The actual antenna and the compact anechoic chamber environment used for testing are as follows: Figure 8 As shown.

[0066] Figure 9 It was tested in the Ku band using an AV3672 vector network analyzer. 11 A comparison chart of the curve results. From Figure 9 As shown in (a), the simulated operating frequency band in the Ku band is 11.1 GHz to 11.78 GHz, and the lowest S within this range 11 It reached -26.45dB, and the measured operating frequency band was 11.08GHz~11.76GHz. From Figure 9 From (b), it can be seen that the simulated operating frequency band of the K band is 19.15GHz to 21.9GHz, and the measured operating frequency band is 19.1GHz to 21.62GHz. At the 20.5GHz frequency point, S 11 The minimum impedance is -25.85dB, indicating good impedance matching.

[0067] Compared with the simulation results, the antenna thickness and patch size may be larger due to the influence of the actual manufacturing process accuracy. This causes the measured impedance bandwidth of the antenna in both frequency bands to shift slightly towards the lower frequency. However, the overall consistency with the simulation is high and meets the design requirements.

[0068] Figure 10 This is a comparison chart of port isolation between the Ku band and the K band. Figure 10 (a) represents the port isolation when the Ku antenna is working alone. The simulated and measured isolation in the operating frequency band are both higher than 25dB. Figure 10 (b) represents the port isolation when the K antenna is working alone. The simulated and measured isolation within the operating frequency band are both higher than 25dB, indicating that the antenna isolation is consistent and has excellent isolation performance.

[0069] The gain pattern of the Ku band at 11.5 GHz is shown below. Figure 11 As shown, in the simulation results, the antenna gain reached 13.65 dBi, the 3 dB beamwidth was ±37.8°, and the directivity was good. In the actual measured results, the gain reached 12.3 dBi, slightly lower than the simulation data, and the sidelobe level increased compared to the simulation results. This is because the error generated during the manufacturing process caused the unit feed phase to be inconsistent, resulting in different superpositions of the radiated electric field arriving at a certain point in space due to different phases.

[0070] In the K-band, right-hand circular polarization is required. Therefore, the axial ratio performance of the antenna also needs to be considered in simulation and actual measurement. The axial ratio of the antenna is measured based on the rotating source method. The axial ratio of the antenna is measured by utilizing the high-speed rotation of the linearly polarized antenna and the rotation of the circularly polarized antenna in the azimuth plane.

[0071] Figure 12 (a) shows the polarization pattern of the antenna at Phi = 0°. It can be seen that the right-hand circular polarization gain is 17.9 dBi, and the left-hand circular polarization gain is -40.5 dBi. Figure 12 (b) shows the polarization pattern of the antenna at Phi = 90°. It can be seen that the right-hand circular polarization gain is 17.9 dBi, while the left-hand circular polarization gain is -40.5 dBi. This indicates that the antenna radiates a right-hand circular polarization wave with a high gain of 17.9 dBi, while the cross-polarization reaches -40.5 dBi.

[0072] Figure 13The axial ratio bandwidth diagram for the K-band is shown. Thanks to the sequential rotating feed technology, the simulated axial ratio bandwidth is 19.1GHz to 22GHz, while the experimentally tested axial ratio bandwidth is 19.2GHz to 21.6GHz. The gain at the 20.4GHz frequency point reaches 15.95dBi. Compared with the simulation results, the bandwidth is slightly narrower and the gain is somewhat deteriorated, but the consistency is good, and the circular polarization performance meets the requirements of antenna design.

[0073] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A coplanar Ku / K dual-band common-aperture antenna, characterized in that, include: The first dielectric plate (A1), the second dielectric plate (B1), the metal layer (C1), and the third dielectric plate (D1), arranged sequentially from top to bottom, are connected by a prepreg lamination method. The front side of the first dielectric substrate (A1) is provided with a first radiating patch (A2), a second radiating patch (A3), and a first ground plane; An L-shaped probe (B2) is placed on the front side of the second dielectric substrate (B1); The interior of the metal layer (C1) has an H-shaped slit (C2); The reverse side of the third dielectric substrate (D1) is provided with a first power supply structure (D2), a second power supply structure (D3), and a second ground plane.

2. The coplanar Ku / K dual-band common-aperture antenna according to claim 1, characterized in that, The first radiating patch (A2) is obtained by chamfering the corners of the microstrip rectangle. The first radiating patches (A2) are periodically arranged on the first dielectric substrate (A1), and the spacing between adjacent first radiating patches (A2) is 9.1 mm; The outer chamfer and the inner slot of the second radiating patch (A3) form an L-shaped gap, which is symmetrically distributed with the second radiating patch (A3) as the center; The second radiating patches (A3) are periodically arranged on the first dielectric substrate (A1), and the spacing between adjacent second radiating patches (A3) is 16.4 mm; The first grounding plate is disposed at both ends of the first medium plate (A1).

3. The coplanar Ku / K dual-band common-aperture antenna according to claim 1, characterized in that, The L-shaped probe (B2) is connected to the first feeding structure (D2), and the L-shaped probe (B2) is fed to the second radiating patch (A3) using a non-contact structure.

4. The coplanar Ku / K dual-band common-aperture antenna according to claim 1, characterized in that, The H-shaped slot (C2) and the second feeding structure (D3) are fed by a non-contact structure with the first radiating patch (A2).

5. The coplanar Ku / K dual-band common-aperture antenna according to claim 1, characterized in that, Both the first power divider (D2) and the second power divider (D3) are T-type power dividers. The first power divider (D2) is symmetrically distributed with the center of the third dielectric plate (D1) as the center. The second power divider (D3) is formed by arranging 1-to-4 structures in a 4×4 configuration to form a 1-to-16 structure. The second grounding plate is located at both ends of the third medium plate (D1).

6. The coplanar Ku / K dual-band common-aperture antenna according to claim 1, characterized in that, The first dielectric substrate (A1) is made of F4b material with a dielectric constant of 2.2 and a thickness of 0.508 mm.

7. The coplanar Ku / K dual-band common-aperture antenna according to claim 1, characterized in that, The second dielectric substrate (B1) is an adhesive layer made of FR-25 material with a dielectric constant of 2.45 and a thickness of 0.26 mm.

8. The coplanar Ku / K dual-band common-aperture antenna according to claim 1, characterized in that, The third dielectric substrate (D1) is made of F4b material with a dielectric constant of 2.2 and a thickness of 0.254 mm.

Images