A transmission array antenna based on triangular arrangement

Abstract

The application discloses a transmission array antenna based on a triangular array, which comprises a transmission array surface and a feed source, wherein the feed source is located below the transmission array surface and is used for spatially feeding the transmission array surface; the transmission array surface is composed of N transmission array units arranged in a triangular array; the transmission array unit is a multi-layer superposition structure, which comprises, from top to bottom, a transmitting layer, a first dielectric substrate, a grounding layer, a second dielectric substrate and a receiving layer; a first metallized via hole is formed in the center of the first dielectric substrate, and the top of the first metallized via hole is connected with the center of the transmitting layer; a via hole is formed in the center of the grounding layer, and a second metallized via hole is formed in the center of the second dielectric substrate, and the bottom of the second metallized via hole is connected with the center of the receiving layer. The transmission array antenna can accommodate more units under the same aperture, and the unit period is small, so that the transmission amplitude and the working bandwidth of the transmission array unit are improved.

Description

Technical Field

[0001] This invention belongs to the field of antenna technology and relates to a transmission array antenna based on a triangular array. Background Technology

[0002] A transmission array antenna mainly consists of a feed and a transmission array. The spherical wave emitted by the feed illuminates the planar transmission array. Due to the different paths the wave takes to reach each element on the array, there is a certain phase difference between the elements. By controlling the phase shift of each element on the array, the electromagnetic wave forms an in-phase wavefront after passing through the transmission array, thus achieving high-gain beam radiation into free space. Compared with traditional high-gain antennas, transmission array antennas have advantages such as light weight, small size, and low cost. Furthermore, the space-feeding method used in transmission array antennas eliminates the losses caused by the feeding network of large array antennas, improving the antenna's radiation efficiency.

[0003] Circularly polarized transmission array antennas offer advantages such as directional transmission, interference suppression, flexibility, and high efficiency, making them promising for applications in communications, radar, and antenna technology. Existing circularly polarized transmission arrays utilize two types of feed sources: linearly polarized feed sources and circularly polarized feed sources. The first type uses a circularly polarized feed source to illuminate the transmission array surface. This type of transmission array achieves phase compensation by changing the size of the elements; however, this alters or even degrades the transmission coefficient, making it difficult to achieve low insertion loss elements over a wide bandwidth. Therefore, this type of transmission array has a narrow bandwidth and low aperture efficiency. The second type is the transmission array that uses linearly polarized feed illumination for linear-to-circular polarization conversion. There are two main types of transmission units: one type has the same patch structure for the receiving and transmitting layers, and circular polarization is achieved by sequentially rotating the transmitting layer patch. This method is based on the principle of electromagnetic wave polarization decomposition. When adjusting the phase of the circularly polarized wave, only one rotation direction phase compensation is considered, resulting in a loss of half the energy and reducing the antenna aperture efficiency. The other type has a circularly polarized patch for the transmitting layer and a linearly polarized patch for the receiving layer. The two have different structures. In order to achieve low insertion loss over a wide bandwidth, it is necessary to achieve good matching between the upper and lower units.

[0004] However, in existing technologies, the metal vias in most cell structures are not located at the cell center. Because phase compensation requires rotating the cell's emitter patch, cells with non-centered metal vias need a larger cell period to prevent the patch from exceeding the cell's period during rotation. Increasing the cell period can negatively impact cell performance to some extent. Summary of the Invention

[0005] The purpose of this invention is to provide a transmission array antenna based on a triangular array. The technical solution adopted by this invention is as follows:

[0006] A transmission array antenna based on a triangular array includes a transmission array and a feed source, wherein the feed source is located below the transmission array and is used to spatially feed the transmission array.

[0007] The transmission array consists of N transmission array elements arranged in a triangular array, where N is a natural number greater than zero.

[0008] The transmission array unit is a multi-layer stacked structure, which includes, from top to bottom, a transmitting layer, a first dielectric substrate, a ground layer, a second dielectric substrate, and a receiving layer;

[0009] A first metallized via is formed at the center of the first dielectric substrate, and the top of the first metallized via is connected to the center of the emitter layer.

[0010] An isolation through-hole is formed at the center of the grounding layer;

[0011] A second metallized via is formed at the center of the second dielectric substrate, and the bottom of the second metallized via is connected to the center of the receiving layer.

[0012] In one embodiment of the present invention, the diameter of the isolation via is greater than the diameters of the first metallized via and the second metallized via.

[0013] In one embodiment of the present invention, the emitting layer includes an emitting patch and an open circular resonant ring, the open circular resonant ring being located on the outer periphery of the emitting patch;

[0014] The emitting patch includes a circular emitting patch and an annular emitting patch located on the outer periphery of the circular emitting patch, and the circular emitting patch and the annular emitting patch are connected by an emitting connector.

[0015] The circular emitter patch is connected to the top of the first metallized through-hole.

[0016] In one embodiment of the present invention, the opening of the open circular resonant ring is positioned in the same direction as the transmitting connection piece.

[0017] In one embodiment of the present invention, the annular emitting patch has patches of the same shape and size removed from both ends of the same diameter to form two concave structures, and the emitting connecting piece forms a 45° angle with one of the concave structures.

[0018] In one embodiment of the present invention, the receiving layer includes a circular receiving patch and an annular receiving patch located on the outer periphery of the circular receiving patch. The circular receiving patch and the annular receiving patch are connected by a receiving connecting piece. The circular receiving patch is connected to the bottom of the second metallized through hole. The direction of the receiving connecting piece is the same as the polarization direction of the received electromagnetic wave.

[0019] In one embodiment of the present invention, when simulating the transmission array unit, the first dielectric substrate, the ground layer, and the second dielectric substrate are all configured as rhombuses.

[0020] In one embodiment of the present invention, the feed source is a linearly polarized pyramidal horn antenna used to generate Y-polarized waves, and the phase center of the horn antenna is located at the focal point of the transmission array.

[0021] In one embodiment of the present invention, the transmission array is a circular array, and the focal diameter ratio of the transmission array is 1.

[0022] The beneficial effects of this invention are:

[0023] The transmission array antenna of the present invention uses several transmission array elements arranged in a triangular layout, which allows more elements to be accommodated under the same aperture. While shortening the element period, it improves the transmission amplitude and operating bandwidth of the transmission array elements, and solves the technical problems of narrow operating bandwidth and low aperture efficiency in the prior art. Attached Figure Description

[0024] Figure 1 This is an overall structural diagram of a transmission array antenna based on a triangular array provided in an embodiment of the present invention;

[0025] Figure 2 This is a schematic diagram of the transmission array structure provided in an embodiment of the present invention;

[0026] Figure 3 This is an overall structural diagram of the transmission array unit provided in an embodiment of the present invention;

[0027] Figure 4 This is a schematic diagram of the structure of the emission layer provided in an embodiment of the present invention;

[0028] Figure 5 This is a schematic diagram of the receiving layer provided in an embodiment of the present invention;

[0029] Figure 6 This is a reflection coefficient diagram of an embodiment of the present invention;

[0030] Figure 7 This is a transmission coefficient diagram of an embodiment of the present invention;

[0031] Figure 8 This is a diagram showing the oblique incidence performance of the xoz plane in an embodiment of the present invention;

[0032] Figure 9 This is a diagram showing the oblique incidence performance of the yoz plane in an embodiment of the present invention;

[0033] Figure 10This is a normalized gain pattern of the xoz and yoz planes at 10 GHz according to an embodiment of the present invention;

[0034] Figure 11 This is a gain diagram of an embodiment of the present invention;

[0035] Figure 12 This is a axial ratio diagram of an embodiment of the present invention.

[0036] Explanation of reference numerals in the attached figures:

[0037] 1. Transmission array; 2. Feed source; 1-1. Transmission array unit; 1-1a. First dielectric substrate; 1-1b. Second dielectric substrate; 1-1c. Transmitter patch; 1-1d. Open circular resonant ring; 1-1e. Ground layer; 1-1f. Receiver layer; 1-1g. First metallized via; 1-1h. Second metallized via; 1-1i. Isolation via. Detailed Implementation

[0038] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0039] An embodiment of the present invention provides a transmission array antenna based on a triangular array, as shown in the attached figure. Figure 1 The transmission array antenna includes a transmission array 1 and a feed 2. The feed 2 is located below the transmission array 1 and is used to spatially feed the transmission array 1. In this embodiment of the invention, the feed 2 is a linearly polarized pyramidal horn antenna used to generate Y-polarized waves. The phase center of the horn antenna is located at the focal point of the transmission array.

[0040] See attached document Figure 2 In this embodiment of the invention, the transmission array 1 consists of N transmission array elements 1-1 arranged in a triangular array, where N is a natural number greater than zero, and the specific number needs to be determined according to the actual situation. This embodiment has 239 transmission array elements, each element 1-1 being a rhombus shape, extending in two directions from a periodic boundary condition, with each element spaced 60° apart in an equilateral triangular arrangement. This transmission array can receive Y-polarized waves, reflect X-polarized waves, and convert the received Y-polarized waves into high-gain, wide-bandwidth, left-hand circularly polarized transmitted waves.

[0041] In this embodiment of the invention, the transmission array 1 is a circular array with a diameter of 204 mm. The feed 2 has an aperture of 68 mm × 48 mm and uses a WR75 waveguide. The focal-to-diameter ratio of the transmission array 1 is 1. The focal-to-diameter ratio is the ratio of the focal length between the feed 2 and the transmission array 1 to the diameter of the transmission array 1.

[0042] See attached document Figure 3The transmission array unit 1-1 in this embodiment of the invention has a multi-layer stacked structure, comprising, from top to bottom, a transmitting layer, a first dielectric substrate 1-1a, a ground layer 1-1e, a second dielectric substrate 1-1b, and a receiving layer. A first metallized via 1-1g is formed at the center of the first dielectric substrate 1-1a, and the top of the first metallized via 1-1g is connected to the center of the transmitting layer. A second metallized via 1-1h is formed at the center of the second dielectric substrate 1-1b, and the bottom of the second metallized via 1-1h is connected to the center of the receiving layer 1-1f.

[0043] To achieve better transmission performance, the radii of the first metallized via 1-1g and the second metallized via 1-1h are usually set to be the same. In this embodiment, the radii of both the first metallized via 1-1g and the second metallized via 1-1h are 0.3mm. To prevent the first metallized via 1-1g and the second metallized via 1-1h from contacting the ground layer 1-1e and affecting the transmission performance of the transmission array unit, an isolation via 1-1i is formed in the center of the ground layer 1-1e. The diameter of the isolation via 1-1i is larger than the diameter of the first metallized via 1-1g and the second metallized via 1-1h. The function of the isolation via 1-1i is to prevent the ground layer 1-1e from contacting the first metallized via 1-1g and the second metallized via 1-1h, thus avoiding affecting the transmission characteristics. In this embodiment of the invention, a via with a diameter of 1.6mm is drilled in the center of the ground layer 1-1e. The first metallized via 1-1g and the second metallized via 1-1h can pass through the isolation via 1-1i without contact. The isolation via 1-1i is also arranged in a triangular array.

[0044] See attached document Figure 4 The emitting layer includes an emitting patch 1-1c and an open circular resonant ring 1-1d, with the open circular resonant ring 1-1d located on the outer periphery of the emitting patch 1-1c. The emitting patch 1-1c of the present invention includes a circular emitting patch and an annular emitting patch located on the outer periphery of the circular emitting patch, the circular emitting patch and the annular emitting patch being connected by an emitting connector. The circular emitting patch is connected to the top of the first metallized via 1-1g. The annular emitting patch has patches of the same shape and size removed from both ends of the same diameter, forming two concave structures. To achieve circular polarization, the rectangular emitting connector forms a 45° angle with one of the concave structures. Preferably, in this embodiment, the patches of the same shape and size removed are rectangular patches of 1.2mm × 1.3mm.

[0045] In an embodiment of the present invention, the radius of the circular emitting patch is 0.72 mm, and the outer radius of the annular emitting patch is 3.4 mm and the inner radius is 1.4 mm.

[0046] In this embodiment, the open circular resonant ring 1-1d is a ring with openings at both ends, and the openings of the open circular resonant ring 1-1d are aligned with the direction of the transmitting connector. The outer radius of the ring is 4.5 mm, and the inner radius is 4 mm. There is a 0.5 mm wide gap in the same direction as the transmitting connector of the transmitting patch 1-1c. The open circular resonant ring of this invention significantly improves the performance of the transmission array unit in a triangular layout compared to a conventional array, substantially increasing the transmission amplitude and operating bandwidth of the transmission array unit, and enhancing the resonance between units, thereby increasing the transmission performance of the unit.

[0047] In the embodiments of the present invention, when simulating the transmission array unit, the first dielectric substrate 1-1a, the ground layer 1-1e, and the second dielectric substrate 1-1b are all set as rhombuses, with a side length of 12mm. The triangular array of the present invention refers to the transmission array units on a transmission array surface being arranged in a triangle. During simulation, the transmission array units need to be simulated first. Using periodic boundary conditions, extending infinitely in two directions, to ensure a triangular relationship between the transmission array units, the dielectric substrate of the simulated transmission array unit needs to be set as a rhombus.

[0048] The emitter patch 1-1c and the open circular resonant ring 1-1d of the emitter layer are applied to the upper surface of the first dielectric substrate 1-1a. The first dielectric substrate 1-1a and the second dielectric substrate 1-1b are made of Arlon TC350 material with a dielectric constant of 3.5, a loss tangent of 0.002, and a thickness of 1.5 mm.

[0049] See attached document Figure 5 The receiving layer 1-1f is applied to the lower surface of the second dielectric substrate 1-1b. In this embodiment, the receiving layer 1-1f includes a circular receiving patch and an annular receiving patch located around the outer periphery of the circular receiving patch. The circular receiving patch and the annular receiving patch are connected by a receiving connecting piece. The circular receiving patch is connected to the bottom of the second metallized via 1-1i. The receiving connecting piece has the same polarization direction as the received electromagnetic wave, receiving electromagnetic waves with the same polarization direction as the receiving connecting piece, while reflecting electromagnetic waves in other directions.

[0050] In this embodiment of the invention, both the transmitting and receiving connectors are rectangular connectors, which offer the best transmission performance compared to other shapes.

[0051] In this embodiment of the invention, the radius of the circular receiving patch is 0.52 mm, the outer radius of the annular receiving patch is 3.55 mm, and the inner radius of the annular receiving patch is 1.7 mm. In this example, the receiving layer receives the Y-polarized wave emitted by the feed source, therefore the direction of the receiving connector is parallel to the Y-axis.

[0052] In this embodiment of the invention, both the transmitting and receiving layers are circular patches. The transmitting and receiving patches are located at the center of the transmission array unit, and the power supply center is located at the center of the transmission array unit. When rotating the patches for phase compensation, a large unit period is not required.

[0053] The technical results of this invention are further illustrated below through simulation experiments:

[0054] Simulation conditions and content: The simulation uses the existing simulation software HFSS to establish an equivalent model.

[0055] Simulation 1 simulates the reflection coefficient and transmission coefficient of the circularly polarized transmission array unit 1-1 in this example. The results of the reflection coefficient of the circularly polarized transmission array unit 1-1 in this embodiment are shown in the attached figure. Figure 6 As shown; the transmission coefficient results of the circularly polarized transmission array unit 1-1 in this embodiment are attached. Figure 7 As shown.

[0056] From the appendix Figure 6 and attached Figure 7 As can be seen, in this embodiment, the reflection coefficient of the circularly polarized transmission array antenna element under X-polarized wave incident light is close to 0dB in the 9.5-12.5GHz frequency band, and the reflection coefficient under Y-polarized wave incident light is less than -10dB, and less than 15dB in the 10GHz-12GHz frequency band. This indicates that the incident X-polarized wave is almost completely reflected, while the incident Y-polarized wave is basically transmitted. As can be seen from the transmission coefficient graph, the transmitted Y-polarized wave is basically converted into a left-hand circularly polarized wave, while the right-hand circularly polarized wave is almost non-existent.

[0057] Simulation 2 simulates the transmission coefficient of the circularly polarized transmission array unit in this embodiment under Y-polarized wave illumination at different oblique incident angles. The results are shown in the appendix. Figure 8 and attached Figure 9 . Figure 8 This is a diagram showing the oblique incidence performance of the xoz plane in an embodiment of the present invention; Figure 9 This is a diagram showing the oblique incidence performance of the yoz plane in an embodiment of the present invention.

[0058] From the appendix Figure 8 and attached Figure 9 As can be seen, in this embodiment, when the oblique incident angle of the Y-polarized wave changes from 0° to 30°, the transmission amplitude of the Y-polarized wave in the 9.5-12.5GHz frequency band is always greater than -1.5dB. This indicates that the transmission characteristics of the transmission array unit remain good when the oblique incident angle of the Y-polarized wave changes.

[0059] Simulation 3 simulates the normalized gain patterns of the circularly polarized folded transmission array antenna in the xoz and yoz planes at 10 GHz in this embodiment. The results are attached. Figure 10As shown.

[0060] From the appendix Figure 10 As can be seen, in this example, the main beams of the E-plane and H-plane of the 239 elements at 10 GHz point to the 0° direction, the 3dB beamwidth is less than 10°, the normalized cross-polarization is less than -20dB, and the sidelobe level is less than -20dB.

[0061] Simulation 4 simulates the gain and axial ratio of the circularly polarized transmission array antenna in this embodiment. The results are shown in the appendix. Figure 11 and attached Figure 12 .

[0062] From the appendix Figure 11 As can be seen, the 239-element circularly polarized transmission array antenna in this embodiment has a 1dB gain bandwidth of 20.1% and an aperture efficiency of 64.2%. (See attached...) Figure 12 It can be seen that the 3dB axial ratio bandwidth covers 9.5GHz-12GHz. This is a significant advantage compared to the 14.8% gain bandwidth and 47.5% aperture efficiency reported in the reference.

[0063] The simulation results above demonstrate that the circularly polarized transmission array antenna of the present invention achieves the function of transmitting circularly polarized beams in a wide frequency band, and the transmission array antenna has a large aperture efficiency.

[0064] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. All content that does not depart from the technical solution of the present invention should be included within the protection scope of the present invention.

Claims

1. A transmission array antenna based on a triangular array, characterized in that: It includes a transmission array (1) and a feed source (2), wherein the feed source (2) is located below the transmission array (1) and is used to spatially feed the transmission array (1); The transmission array (1) consists of N transmission array units (1-1) arranged in a triangular array, where N is a natural number greater than zero. The transmission array unit (1-1) has a multi-layer stacked structure, which includes, from top to bottom, a transmitting layer, a first dielectric substrate (1-1a), a ground layer (1-1e), a second dielectric substrate (1-1b), and a receiving layer (1-1f). A first metallized via (1-1g) is formed at the center of the first dielectric substrate (1-1a), and the top of the first metallized via (1-1g) is connected to the center of the emitter layer. An isolation via (1-1i) is formed at the center of the grounding layer (1-1e). A second metallized via (1-1h) is formed at the center of the second dielectric substrate (1-1b), and the bottom of the second metallized via (1-1h) is connected to the center of the receiving layer (1-1f). The emitting layer includes an emitting patch (1-1c) and an open circular resonant ring (1-1d), wherein the open circular resonant ring (1-1d) is located on the outer periphery of the emitting patch (1-1c); The emitting patch (1-1c) includes a circular emitting patch and an annular emitting patch located on the outer periphery of the circular emitting patch, and the circular emitting patch and the annular emitting patch are connected by an emitting connecting piece; The circular emitter patch is connected to the top of the first metallized through-hole (1-1g).

2. The transmission array antenna based on a triangular array according to claim 1, characterized in that, The diameter of the isolation via (1-1i) is greater than the diameters of the first metallized via (1-1g) and the second metallized via (1-1h).

3. The transmission array antenna based on a triangular array according to claim 1, characterized in that, The opening of the open circular resonant ring (1-1d) is positioned in the same direction as the transmitting connector.

4. The transmission array antenna based on a triangular array according to claim 1, characterized in that, The annular emitting patch has patches of the same shape and size removed from both ends of the same diameter to form two concave structures, and the emitting connecting piece forms a 45° angle with one of the concave structures.

5. The transmission array antenna based on a triangular array according to claim 1, characterized in that, The receiving layer (1-1f) includes a circular receiving patch and an annular receiving patch located on the outer periphery of the circular receiving patch. The circular receiving patch and the annular receiving patch are connected by a receiving connecting piece. The circular receiving patch is connected to the bottom of the second metallized through-hole (1-1h). The direction of the receiving connecting piece is the same as the polarization direction of the received electromagnetic wave.

6. The transmission array antenna based on a triangular array according to any one of claims 1-5, characterized in that, When simulating the transmission array unit (1-1), the first dielectric substrate (1-1a), the ground layer (1-1e), and the second dielectric substrate (1-1b) are all set to a rhombus shape.

7. The transmission array antenna based on a triangular array according to claim 6, characterized in that, The feed (2) uses a linearly polarized pyramidal horn antenna to generate Y-polarized waves, and the phase center of the horn antenna is located at the focal point of the transmission array (1).

8. The transmission array antenna based on a triangular array according to claim 6, characterized in that, The transmission array (1) is a circular array, and the focal diameter ratio of the transmission array (1) is 1.

Images