Dual-band dual-circularly polarized antenna array

Abstract

The application relates to the technical field of wireless communication, in particular to a dual-frequency dual-circular polarization antenna array. The antenna array comprises at least one array unit group, the array unit group comprises at least one array unit, and the array unit comprises: a plurality of first patches arranged uniformly in a first circle, adjacent first patches having equal first phase differences; a plurality of second patches arranged uniformly in a second circle, adjacent second patches having equal second phase differences; the first circle and the second circle are concentric circles, the radius of the second circle is greater than the radius of the first circle, and each second patch is located between two adjacent first patches in the radial direction; a first feeding network, an input end of the first feeding network being connected with a first feeding point, and output ends of a plurality of first feeding networks being respectively connected with the plurality of first patches for feeding; and a second feeding network, an input end of the second feeding network being connected with a second feeding point, and output ends of a plurality of second feeding networks being respectively connected with the plurality of second patches for feeding.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and in particular to dual-frequency dual-circularly polarized antenna arrays. Background Technology

[0002] With the rapid development of wireless communication technology, satellite communication is increasingly widely used globally, especially in fields such as long-distance communication, satellite navigation, military reconnaissance, and meteorological monitoring, where the performance requirements for satellite communication systems are constantly increasing. Traditionally, satellite communication mainly uses the C-band (4GHz-8GHz) and Ku-band (12GHz-18GHz) for signal transmission. However, with increasing user demand and data throughput, resources in these frequency bands are gradually becoming scarce, and spectrum congestion is becoming increasingly serious. To address this challenge, the Ka-band (26.5GHz-40GHz), due to its wider bandwidth, higher data rate, and better spectrum utilization, has become an important direction for the development of satellite communication technology.

[0003] In Ka-band satellite communication systems, antenna performance plays a crucial role in the stability and transmission quality of the entire communication link. However, due to the high frequency of the Ka-band, its electromagnetic wave transmission faces several major technical challenges:

[0004] 1. Significant path loss. As the frequency increases, the free-space propagation loss of electromagnetic waves increases significantly, requiring antennas to have better gain to compensate for the loss;

[0005] 2. Weather attenuation has a significant impact. Ka-band signals are greatly affected by rain attenuation, cloud attenuation, and water vapor absorption in the atmosphere, especially under severe weather conditions, where signal quality is easily degraded.

[0006] 3. High requirements for antenna size and integration. Traditional parabolic antennas are large and heavy, making them unsuitable for applications such as small satellites, drones, and mobile terminals.

[0007] Therefore, there is an urgent need for a means to achieve antenna miniaturization, improve gain, and facilitate integration. Utility Model Content

[0008] The purpose of this application is to provide a dual-frequency dual-circular polarized antenna array that enables antenna miniaturization, improves gain, and is easy to integrate.

[0009] This application discloses a dual-frequency dual-circularly polarized antenna array, the antenna array comprising at least one array element group, the array element group comprising at least one array element, the array element comprising: a plurality of first patches uniformly arranged on a first circumference, adjacent first patches having an equal phase difference; a plurality of second patches uniformly arranged on a second circumference, adjacent second patches having an equal phase difference; the first circumference and the second circumference are concentric circles, the radius of the second circumference is greater than the radius of the first circumference, and each second patch is radially located between two adjacent first patches; a first feed network comprising an input terminal and a plurality of output terminals, the input terminal of the first feed network being connected to a first feed point, the output terminals of the plurality of first feed networks being respectively fed to the plurality of first patches; and a second feed network comprising an input terminal and a plurality of output terminals, the input terminal of the second feed network being connected to a second feed point, the output terminals of the plurality of second feed networks being respectively fed to the plurality of second patches.

[0010] In this solution, since the radius of the second circumference is greater than that of the first circumference, the first circumference is located inside the second circumference. Multiple first patches are arranged on the inner side of the first circumference, and multiple second patches are arranged on the outer side of the second circumference. Furthermore, each second patch is located radially between two adjacent first patches, which can effectively utilize space, has a compact arrangement, small overall size, and is easy to integrate.

[0011] The first and second feeding networks respectively feed multiple first patches and multiple second patches, such that each first patch has an equal first phase difference relative to its adjacent first patch, and each second patch has an equal second phase difference relative to its adjacent second patch. This allows both the first and second patches to employ sequential rotation technology, strengthening the common polarization field while canceling out the cross-polarization fields, thus improving polarization purity and enabling the antenna array to operate within a wide aspect ratio frequency band. The first patch can be used to transmit signals in the first frequency band, and the second patch can be used to transmit signals in the second frequency band, thereby providing dual-frequency dual-circular polarization functionality. This is suitable for applications requiring dual polarization, such as satellite communication. Furthermore, circularly polarized antennas offer more stable signals during multipath effects and the movement of satellites and ground stations, and are less susceptible to atmospheric attenuation from rain, clouds, and water vapor absorption. The high gain of dual-frequency dual-circular polarization can compensate for path loss.

[0012] In some embodiments, the radiation area of ​​the first patch is smaller than that of the second patch, and the area of ​​the first patch located on the inner first circumference is even smaller, which can make more efficient use of space; and the areas of the first patch and the second patch are different, so they can operate in different frequency bands; the first patch is a right-hand circularly polarized patch, which can be used to transmit uplink signals, and the second patch is a left-hand circularly polarized patch, which can be used to transmit downlink signals, thereby enabling bidirectional transmission. Attached Figure Description

[0013] Figure 1A A three-dimensional structural schematic diagram of an antenna array according to an embodiment of this application is shown;

[0014] Figure 1B A plan view of an array cell according to an embodiment of this application is shown;

[0015] Figure 1C A plan view of a first patch and a second patch according to an embodiment of this application is shown;

[0016] Figure 1D A schematic diagram of four types of patches according to an embodiment of this application is shown;

[0017] Figures 1E to 1H Performance simulation diagrams of an array cell according to an embodiment of this application are shown respectively;

[0018] Figure 2A A schematic diagram of a first feed network and a second feed network according to an embodiment of this application is shown;

[0019] Figure 2B A schematic diagram of two power dividers according to an embodiment of this application is shown;

[0020] Figure 2C Schematic diagrams of two power supply configurations according to an embodiment of this application are shown;

[0021] Figures 2D to 2I Performance simulation diagrams of a first feeder network and a second feeder network according to an embodiment of this application are shown respectively;

[0022] Figures 3A to 3J Performance schematic diagrams of an array cell according to an embodiment of this application are shown respectively;

[0023] Figure 4 A schematic diagram of an array cell group according to another embodiment of this application is shown. Detailed Implementation

[0024] To make the objectives and technical solutions of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the described embodiments of this application without creative effort are within the scope of protection of this application.

[0025] Figure 1A A three-dimensional structural schematic diagram of an antenna array according to an embodiment of this application is shown. Figure 1B A planar schematic diagram of an array cell according to an embodiment of this application is shown. Figure 1C A planar schematic diagram of a first patch and a second patch according to an embodiment of this application is shown. The following is in conjunction with... Figures 1A to 1C The antenna array of this embodiment is described below. The XYZ coordinate axes shown in the figure are a rectangular coordinate system, where the Z-axis is perpendicular to the radiating surface of the antenna array.

[0026] like Figure 1A and Figure 1B As shown, the dual-band dual-circular polarized antenna array 1 includes at least one array element group 10, and each array element group 10 includes at least one array element 100. Each array element 100 includes a plurality of first patches 101 and a plurality of second patches 102. In this embodiment, the antenna array 1 includes one array element group 10, which includes one array element 100, and the array element 100 includes four first patches 101 and four second patches 102. It should be understood that the above quantities are merely illustrative. In other embodiments, the antenna array 1 may include two or more array element groups 10, and each array element group 10 may also include two or more array elements 100; at the same time, the number of first patches 101 and second patches 102 is not limited to four, and may also be other numbers (e.g., eight each), as long as they are uniformly arranged on their respective circumferences and achieve the required phase relationship.

[0027] like Figure 1A As shown, the array unit 100 further includes a first feed network 103 and a second feed network 104. The first feed network 103 includes an input terminal and multiple output terminals. The input terminal of the first feed network 103 is connected to a first feed point 106, and the multiple output terminals of the first feed network 103 are respectively fed to multiple first patches 101, providing signals with a predetermined phase relationship to each first patch 101. The second feed network 104 includes an input terminal and multiple output terminals. The input terminal of the second feed network 104 is connected to a second feed point 107, and the multiple output terminals of the second feed network 104 are respectively fed to multiple second patches 102, providing signals with a predetermined phase relationship to each second patch 102.

[0028] In this embodiment, the array unit 100 is square, for example, the length and width can both be 3cm, which can be conveniently arranged.

[0029] like Figure 1C As shown, multiple first patches 101 are uniformly arranged on a first circumference c1, and multiple second patches 102 are uniformly arranged on a second circumference c2. The first circumference c1 and the second circumference c2 are concentric circles, and the center o of these concentric circles can be the geometric center of the array unit 100. As an example, the array unit 100 is a square, and its geometric center is at the exact center of the square. The radius of the second circumference c2 is larger than the radius of the first circumference c1, the first circumference c1 is located inside the second circumference c2, and each second patch 102 is radially positioned between two adjacent first patches 101. See also... Figure 1C A radial line l2, originating from the geometric center o of the array unit 100 and passing through the center of the second patch 102, is located between two radial lines l1, originating from the geometric center and passing through the centers of two adjacent first patches 101. This arrangement allows the first patches 101 and the second patches 102 to be arranged in a radially staggered manner, effectively improving space utilization. The patch arrangement is compact, the overall size is small, and it is easy to integrate.

[0030] To ensure that no grating lobes appear in the phase antenna array during beam scanning, the spacing between adjacent patches and the scanning angle should satisfy the following constraint relationship:

[0031]

[0032]

[0033] in, , These represent the spacing between adjacent patches in the X and Y directions, respectively. , These represent the maximum scanning angles of the antenna array along the X and Y directions, respectively. The wavelength of the transmitted signal.

[0034] like Figure 1C As shown, the spacing between adjacent first patches in the X direction is dx, and the spacing in the Y direction is dy. Through simulation, the magnitudes of the spacings dx and dy can be determined, and it is confirmed that the spacing dx is equal to the spacing dy. Figure 1E A planar simulation diagram of a second patch according to an embodiment of this application is shown. Figure 1EAs shown, the spacing between adjacent second patches in the X direction is dx, and the spacing in the Y direction is dy. Through simulation, the magnitudes of the spacings dx and dy can be determined, and it is confirmed that the spacing dx is equal to the spacing dy. The spacing between adjacent patches in the X direction is equal to the spacing in the Y direction, which improves the symmetry of the antenna pattern and the purity of circular polarization.

[0035] Adjacent first patches 101 have an equal first phase difference, see Figure 1C With four first patches 101 arranged, the first phase difference is 90°, and the feed phases of the first first patch 1011 to the fourth first patch 1014 are 0°, 90°, 180°, and 270° respectively. Adjacent second patches 102 have equal second phase differences, that is, each second patch 102 has an equal second phase difference relative to its adjacent second patch 102. See [link to documentation] Figure 1C With four second patches 102 arranged, the second phase difference is 90°, and the feed phases of the first second patch 1021 to the fourth second patch 1024 are 0°, 90°, 180° and 270° respectively.

[0036] In some embodiments, adjacent patches are physically rotated by 90° and the feed phase is sequentially increased by 90° to achieve sequential rotation. By employing sequential rotation, the phases between adjacent patches change sequentially, the common polarization field is strengthened, and the cross polarization fields are canceled out, which can improve polarization purity and enable the array unit to operate in a wide aspect ratio frequency band.

[0037] Each first patch 101 and second patch 102 constitutes a circularly polarized radiating element. The first patch 101 can be used to transmit signals, and the second patch 102 can be used to transmit signals in a second frequency band. In some embodiments, the first frequency band (e.g., a center frequency of approximately 30 GHz) is higher than the second frequency band (e.g., a center frequency of approximately 20 GHz). The first patch 101 is used to transmit uplink signals, and the second patch 102 is used to transmit downlink signals, thereby achieving dual-frequency operation. Thus, this antenna array has dual-frequency dual-circular polarization functionality, suitable for applications requiring dual polarization, such as satellite communication. Furthermore, the circularly polarized antenna provides more stable signals during multipath effects and the movement of the satellite and ground station, and is less susceptible to atmospheric attenuation from rain, clouds, and water vapor absorption. The high gain of the dual-frequency dual-circular polarization can compensate for path loss.

[0038] In some embodiments, the first patch 101 is a right-hand circular polarization (RHCP) patch, and the second patch 102 is a left-hand circular polarization (LHCP) patch. Figure 1D As shown, the shape of the first patch 101 can be a slit rectangular patch, a slit circular patch, a chamfered rectangular patch, or a chamfered circular patch, and the shape of the second patch 102 can be a slit rectangular patch, a slit circular patch, a chamfered rectangular patch, or a chamfered circular patch. Figure 1C In the example, both the first patch 101 and the second patch 102 are chamfered rectangular patches. By controlling the direction of the cut, the direction of the chamfer, or the direction of the feed point, right-hand circular polarization or left-hand circular polarization can be achieved. As an example, the first patch 101 achieves right-hand circular polarization by using the lower right corner feed point or a clockwise chamfer, and the second patch 102 achieves left-hand circular polarization by using the lower left corner feed point or a counterclockwise chamfer.

[0039] In some embodiments, the surface area of ​​the first patch 101 is smaller than that of the second patch 102, meaning the radiating area of ​​the first patch 101 is smaller than that of the second patch 102. Since the frequency of a patch is inversely proportional to its area, the smaller surface area of ​​the first patch 101 compared to the second patch 102 naturally allows it to operate at a higher frequency. This size difference not only enables the antenna array to support dual-band operation but also allows the inner first patch 101 to more efficiently utilize the central area of ​​the array unit, improving the overall layout compactness and integration.

[0040] Figures 1E to 1H The following are performance simulation diagrams of an array cell according to an embodiment of the present application under ideal conditions, wherein the ideal condition refers to the four patches of the up or down direction having equal amplitude and adjacent cells having a phase difference of 90°.

[0041] Figure 1E The simulation graph of return loss at the feed port of the first patch is shown. The horizontal axis represents frequency in GHz, and the vertical axis represents return loss in dB. The center frequency of the first patch is approximately 30 GHz. Figure 1E This indicates that the return loss at the feed port of the first patch is below -10dB in the uplink frequency band (around 30GHz), which means that the VSWR of the array unit is small.

[0042] Figure 1FThe simulation diagram of the axial ratio in the circularly polarized antenna specifications of the first patch is shown. It is the axial ratio in the main direction of the antenna pattern, with both the azimuth angle Phi and the elevation angle Theta at 0°. The horizontal axis is the frequency in GHz, and the vertical axis is the axial ratio in dB. It shows that when both the azimuth and elevation angles are 0°, the axial ratio of the first patch is below 0.2dB, covering a frequency band of 25GHz-35GHz, achieving high polarization purity over a wide bandwidth, and possessing high anti-interference capability and signal quality.

[0043] Figure 1G The simulation graph of return loss at the feed port of the second patch is shown. The horizontal axis represents frequency in GHz, and the vertical axis represents return loss in dB. The center frequency of the second patch is approximately 20 GHz. Figure 1G This indicates that the return loss at the feed port of the second patch is below -10dB in the downlink frequency band (around 20GHz), which means that the VSWR of the array unit is small.

[0044] Figure 1H The diagram shows the axial ratio of the second patch's circularly polarized antenna specifications. It represents the axial ratio along the main direction of the antenna pattern, where both the azimuth (Phi) and elevation (Theta) are 0°. The horizontal axis represents frequency in GHz, and the vertical axis represents the axial ratio in dB. This indicates that with both azimuth and elevation angles at 0°, the axial ratio of the second patch is below 0.15dB, covering a frequency band of 15GHz-25GHz. This achieves high polarization purity over a wide bandwidth, exhibiting high anti-interference capability and signal quality.

[0045] Figure 2A A schematic diagram of a first power supply network and a second power supply network according to an embodiment of this application is shown.

[0046] In some embodiments, the first power supply network 103 and the second power supply network 104 respectively include power divider units 1033 and 1034. The input terminal P1 of the first power supply network 103... com The power divider unit 1033 connects to multiple output terminals P11-P14 of the first feed network to distribute the signal from the first feed point equally and feed it to multiple first patches; the input terminal P2 of the second feed network 104 com Multiple output terminals P21-P24 of the second feed network 104 are connected via power divider unit 1034 to distribute the signal from the second feed point equally and feed it to multiple second patches. As an example, power divider units 1033 and 1034 are both formed of microstrip lines.

[0047] In some embodiments, power divider units 1033 and 1034 each include at least one one-to-many power divider. As an example, such as... Figure 2A As shown, the power divider unit of the first power supply network includes a first power divider 2011 to a third power divider 2013. The first power divider 2011 to the third power divider 2013 are 1-to-2 power dividers to divide the signal from the first feed point into 4 parts with equal amplitude.

[0048] The input terminal of the first power divider 2011 serves as the input terminal P1 of the first power supply network. com A first power divider 2011 is connected to a first feed point, which is used to connect to the baseband to receive transmitted signals from the baseband. The first output of the first power divider 2011 is connected to the input of the second power divider 2012 via a transmission line (e.g., a microstrip line) 1035. The first output of the second power divider 2012 serves as the output P11 of the first feed network and is connected to the first first patch. The second output of the second power divider 2012 serves as the output P12 of the first feed network and is connected to the second first patch via a transmission line. The second output of the first power divider 2011 is connected to the input of the third power divider 2013. The first output of the third power divider 2013 serves as the output P13 of the first feed network and is connected to the third first patch via a transmission line. The second output of the third power divider 2013 serves as the output P14 of the first feed network and is connected to the fourth first patch via a transmission line.

[0049] The transmission line lengths between the first and second output terminals of the first power divider 2011, the second power divider 2012, and the third power divider 2013 all differ by 1 / 4 wavelength, used to compensate for the 90° feed phase difference between adjacent patches. Figure 2A In the diagram, the dashed box is used to indicate the transmission line segments with a 1 / 4 wavelength length difference between the outputs of each power divider.

[0050] In some embodiments, the first power divider 2011 to the third power divider 2013 are all T-type power dividers or Wilkinson power dividers. For example... Figure 2B As shown, the T-type power divider has a simple structure. The Wilkinson power divider has good port isolation and amplitude consistency (high impedance matching consistency), and can more reliably maintain the equal amplitude characteristics of each feed path under phase compensation conditions, thus improving the overall performance and efficiency of the antenna array. P1 is the input terminal of the power divider, and P2 and P3 are the first and second output terminals, respectively. Figure 2A In the example shown, the first power divider 2011 to the third power divider 2013 are all Wilkinson power dividers.

[0051] Continue as Figure 2AAs shown, the power divider unit of the second power supply network includes the fourth power divider 2021 to the sixth power divider 2023. The fourth power divider 2021 to the sixth power divider 2023 are 1-to-2 power dividers, and the fourth power divider 2021 to the sixth power divider 2023 form a 1-to-4 power divider network.

[0052] The input terminal of the fourth power divider 2021 serves as the input terminal P2 of the second power supply network. com The fourth power divider 2021 is connected to the input of the fifth power divider 2022 via a transmission line (e.g., a microstrip line) 1036. The first output of the fifth power divider 2022 serves as the output of the second power supply network, P21, and is connected to the first second patch via the transmission line. The second output of the fifth power divider 2022 serves as the output of the second power supply network, P24, and is connected to the fourth second patch via the transmission line. The second output of the fourth power divider 2021 is connected to the input of the sixth power divider 2023. The first output of the sixth power divider 2023 serves as the output of the second power supply network, P22, and is connected to the second second patch via the transmission line. The second output of the sixth power divider 2023 serves as the output of the second power supply network, P23, and is connected to the third second patch via the transmission line.

[0053] The transmission line lengths between the first and second output terminals of the fourth power divider 2021, the fifth power divider 2022, and the sixth power divider 2023 all differ by 1 / 4 wavelength, used to compensate for the 90° feed phase difference between adjacent patches. Figure 2A In the diagram, the dashed box is used to indicate the transmission line segments with a 1 / 4 wavelength length difference between the outputs of each power divider.

[0054] In some embodiments, the fourth power divider 2021 to the sixth power divider 2023 are all T-type power dividers or Wilkinson power dividers. Figure 2A In the example shown, the fourth power divider 2021 to the sixth power divider 2023 are all Wilkinson power dividers.

[0055] In the above embodiments, power divider units 1033 and 1034 each include three 1-to-2 power dividers. In other embodiments, power divider units 1033 and 1034 may also include a 1-to-4 power divider.

[0056] In some embodiments, the output of the first power supply network is fed to a plurality of first patches via a slot plate or coaxial cable, and the output of the second power supply network is fed to a plurality of second patches via a slot plate or coaxial cable. Figure 2CAs shown, in the case of slot feeding, the slot plate is located between two upper and lower substrates, and the microstrip line and patch (including the first patch or the second patch) are located on opposite sides of the two substrates. The sum of the thicknesses of the two substrates and the slot plate can be 0.71 mm. In the case of coaxial feeding, the coaxial cable is located in the substrate, and the microstrip line and patch (including the first patch or the second patch) are located on opposite sides of the substrate. The thickness of the substrate can be 0.71 mm. In both cases, the microstrip line and the patch (including the first patch or the second patch) are located on different layers. Therefore, the radiated electric field of the microstrip line will not affect the antenna pattern. However, the cross-polarization level of the microstrip antenna in slot feeding is lower than that in coaxial feeding, which is more advantageous for polarization-sensitive applications. Furthermore, slot feeding can achieve a wider operating bandwidth through design, for example, in... Figure 2A In the example shown, the outputs of the first power supply network and the second power supply network are respectively fed to multiple first patches and multiple second patches via a slot plate.

[0057] Figures 2D to 2I Performance simulation diagrams of a first power supply network and a second power supply network according to an embodiment of this application are shown respectively.

[0058] Figure 2D The simulation diagram of return loss at the input and output of the first feed network is shown. The horizontal axis represents frequency in GHz, and the vertical axis represents return loss in dB. It shows that near 30 GHz, the return loss at the input of the first feed network is below -15 dB, and the return loss at the output port is below -10 dB, which is a good match.

[0059] Figure 2E The simulation diagram of insertion loss at the four outputs of the first feed network is shown. The horizontal axis represents frequency in GHz, and the vertical axis represents insertion loss in dB. It shows that the amplitude error between the four outputs of the first feed network is within ±0.5 dB around 30 GHz.

[0060] Figure 2F The simulation diagram of the phase at the four outputs of the first power supply network is shown. The horizontal axis represents frequency in GHz and the vertical axis represents phase in degrees. It shows that the phase difference between the four outputs of the first power supply network is 90° around 30 GHz.

[0061] Figure 2GThe simulation diagram of return loss at the input and output of the second feed network is shown. The horizontal axis represents frequency in GHz, and the vertical axis represents return loss in dB. It shows that near 20 GHz, the return loss at the input of the second feed network is below -15 dB, and the return loss at the output port is below -10 dB, indicating good matching.

[0062] Figure 2H The simulation diagram of insertion loss at the four outputs of the second feed network is shown. The horizontal axis represents frequency in GHz, and the vertical axis represents insertion loss in dB. It shows that the amplitude error between the four outputs of the second feed network is within ±0.5 dB around 20 GHz.

[0063] Figure 2I The simulation diagram of the phase at the four outputs of the second power supply network is shown. The horizontal axis represents frequency in GHz and the vertical axis represents phase in degrees. It shows that the phase difference between the four outputs of the second power supply network is 90° around 20 GHz.

[0064] Figures 3A to 3J Performance schematic diagrams of array cells according to embodiments of this application are shown respectively.

[0065] Figure 3A The diagram shows the return loss at the feed port of the first patch. The horizontal axis represents the frequency in GHz, and the vertical axis represents the return loss in dB. It shows that the return loss at the feed port of the first patch is below -15dB, indicating that the standing wave ratio of the array element is small.

[0066] Figure 3B The diagram shows the axial ratio of the first patch's circularly polarized antenna specifications. It represents the axial ratio along the main direction of the antenna pattern, with both the azimuth (Phi) and elevation (Theta) at 0°. The horizontal axis represents frequency in GHz, and the vertical axis represents axial ratio in dB. This indicates that with both azimuth and elevation at 0°, the first patch's axial ratio ≤ 3dB spans the frequency band of 27.68GHz-32.19GHz, achieving high polarization purity over a wide bandwidth and exhibiting high anti-interference capability and signal quality.

[0067] Figure 3CThe diagram shows the gain of the first patch, representing the antenna's gain performance at 30 GHz with Phi (azimuth angle) at 0° and Theta (elevation angle) within ±180°. The horizontal axis represents the elevation angle Theta in degrees, and the vertical axis represents the gain in dB. It indicates that the main polarization (right-hand circular polarization) main beam gain is 11.45 dB, and the main-sidelobe level ratio is above 15 dB. The gain difference between common polarization and cross-polarization is above 20 dB, indicating that the polarization purity performance meets the standard.

[0068] Figure 3D Another gain diagram of the first patch is shown, representing the antenna gain at different frequencies when both the azimuth angle Phi and the elevation angle Theta are 0° in the main direction. The horizontal axis represents frequency in GHz, and the vertical axis represents gain in dB. It shows that the main beam has a 3dB beamwidth of 30° at 30GHz, and the bandwidth of the main beam gain drops by 3dB from 28.46GHz to 31.73GHz, with a bandwidth of 1.2GHz.

[0069] Figure 3E The antenna pattern of the first patch is shown, with the maximum radiation direction of the first patch along the Z-axis.

[0070] Figure 3F The diagram shows the return loss at the feed port of the second patch. The horizontal axis represents the frequency in GHz, and the vertical axis represents the return loss in dB. It shows that the return loss at the feed port of the second patch is below -15dB, indicating that the standing wave ratio of the array element is small.

[0071] Figure 3G The diagram shows the axial ratio of the second patch's circularly polarized antenna specifications. It represents the axial ratio along the main direction of the antenna pattern, i.e., when both the azimuth (Phi) and elevation (Theta) are 0°. The horizontal axis represents frequency in GHz, and the vertical axis represents axial ratio in dB. This indicates that when both the azimuth and elevation angles are 0°, the axial ratio of the second patch is ≤3dB, spanning a frequency band of 18.66GHz-20.57GHz, achieving high polarization purity over a wide bandwidth.

[0072] Figure 3H The diagram shows the gain of the second patch, representing the antenna's gain performance at 20 GHz with Phi (azimuth) at 0° and Theta (elevation) within ±180°. The horizontal axis represents the polarization angle in degrees, and the vertical axis represents the gain in dB. It indicates that the main polarization (left-hand circular polarization) main beam gain is 11.57 dB, and the main-sidelobe level ratio is above 15 dB. The gain difference between common polarization and cross-polarization is above 20 dB, indicating that the polarization purity performance meets the requirements.

[0073] Figure 3I Another gain diagram of the second patch is shown, illustrating the antenna gain at different frequencies when both the azimuth (Phi) and elevation (Theta) are 0° in the main direction. The horizontal axis represents frequency in GHz, and the vertical axis represents gain in dB. This indicates that the main beam has a 3dB beamwidth of 37° at 20GHz, and the bandwidth decreasing by 3dB from the main beam gain is between 19.09GHz and 20.64GHz, with a total bandwidth of 1GHz.

[0074] Figure 3J The antenna pattern of the second patch is shown, with the maximum radiation direction of the second patch along the Z-axis.

[0075] Figure 4 A schematic diagram of an array cell group according to another embodiment of this application is shown.

[0076] like Figure 4 As shown, the array cell group comprises multiple array cells (subarrays). As an example, Figure 4 Four array units, Subarray1-Subarray4, are shown. However, it is understood that the number of array units, Subarray1, is not limited to four. It can be more or less. For example, the number of array units, Subarray1, can all be eight, as long as the sequence rotation arrangement requirement is met.

[0077] The centers o1-o4 of the four array cells Subarray1-Subarray4 are located on the third circumference c3 and are uniformly arranged. The center of the third circumference c3 is the center of the array cell group. In adjacent array cells Subarray, the lines connecting the second patch with the same feed phase to the center of the third circumference are orthogonal to each other. For example, taking a specific point of a specific patch with the same phase in each array cell (e.g., the second patch 1021) as a reference point, connecting these reference points to the center of the circle yields lines A1-A4, respectively. Adjacent lines are orthogonal to each other. This application will be as follows: Figure 1A The illustrated subarray is a single subarray. Adjacent subarrays are physically rotated by 90° to ensure a 90° phase difference between them, and this is achieved through sequential rotation. This design not only facilitates integration into large phased array radar systems but also maintains high gain and high polarization purity during array expansion, effectively avoiding cross-polarization degradation caused by increased scale.

[0078] It should be noted that in the claims and description of this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0079] Although this application has been illustrated and described with reference to certain preferred embodiments thereof, those skilled in the art should understand that various changes in form and detail may be made thereto without departing from the spirit and scope of this application.

Claims

1. A dual-frequency dual-circular polarization antenna array, characterized in that, The antenna array includes at least one array element group, the array element group includes at least one array element, and the array element includes: Multiple first patches are evenly arranged on a first circumference, and adjacent first patches have an equal first phase difference; Multiple second patches are evenly arranged on a second circumference, with adjacent second patches having an equal second phase difference; the first circumference and the second circumference are concentric circles, the radius of the second circumference is larger than the radius of the first circumference, and each second patch is located radially between two adjacent first patches; A first power supply network includes an input terminal and multiple output terminals. The input terminal of the first power supply network is connected to a first feed point, and the multiple output terminals of the first power supply network are respectively connected to multiple first patch panels; and, The second power supply network includes an input terminal and multiple output terminals. The input terminal of the second power supply network is connected to the second feed point, and the multiple output terminals of the second power supply network are respectively connected to multiple second patch power supplies.

2. The dual-frequency dual-circular polarization antenna array as described in claim 1, characterized in that, The frequency of the first patch is greater than the frequency of the second patch.

3. The dual-frequency dual-circular polarization antenna array as described in claim 1, characterized in that, The surface area of ​​the first patch is smaller than the surface area of ​​the second patch; The first patch is a right-hand circularly polarized patch, and the second patch is a left-hand circularly polarized patch.

4. The dual-frequency dual-circular polarization antenna array as described in claim 1, characterized in that, The array unit includes four first patches and four second patches; the first phase difference and the second phase difference are both 90°. The phases of the first to fourth first patches are 0°, 90°, 180° and 270° respectively; The phases of the first to fourth second patches are 0°, 90°, 180° and 270° respectively.

5. The dual-frequency dual-circular polarization antenna array as described in claim 4, characterized in that, Each array unit group includes four array units, the centers of which are located on a third circumference and are evenly arranged, the center of which is the center of the array unit group; in adjacent array units, the lines connecting the second patch with the same feed phase to the center of the third circumference are orthogonal to each other.

6. The dual-frequency dual-circular polarization antenna array as described in claim 1, characterized in that, Both the first power supply network and / or the second power supply network include power divider units; The input terminal of the first power supply network is connected to multiple output terminals of the first power supply network through the power divider unit, so as to distribute the signal from the first feed point equally and feed it to multiple first patches. And / or, The input of the second power supply network is connected to multiple outputs of the second power supply network through the power divider unit, so as to distribute the signal from the second feed point equally and feed it to multiple second patches.

7. The dual-frequency dual-circular polarization antenna array as described in claim 6, characterized in that, The power divider unit includes at least one one-to-many power divider.

8. The dual-frequency dual-circular polarization antenna array as described in claim 7, characterized in that, The power divider unit of the first power supply network includes a first power divider, a second power divider, and a third power divider, wherein the first power divider, the second power divider, and the third power divider are 1-to-2 power dividers. The first power divider, whose input terminal serves as the input terminal of the first power supply network, is connected to the first feed point; The second power divider has its first output terminal connected to the input terminal of the first power divider; the first output terminal of the second power divider serves as the output terminal of the first power supply network and is connected to the first first patch; the second output terminal of the second power divider serves as the output terminal of the first power supply network and is connected to the second first patch. The third power divider has its second output terminal connected to the input terminal of the first power divider; the first output terminal of the third power divider serves as the output terminal of the first power supply network and is connected to the third first patch; the second output terminal of the third power divider serves as the output terminal of the first power supply network and is connected to the fourth first patch. A 1 / 4 wavelength transmission line is provided between the second output terminal of the first power divider and the input terminal of the third power divider, between the second output terminal of the second power divider and the second first patch, and between the second output terminal of the third power divider and the fourth first patch. And / or, the power divider unit of the second power supply network includes a fourth power divider, a fifth power divider, and a sixth power divider, wherein the fourth power divider, the fifth power divider, and the sixth power divider are 1-to-2 power dividers: The fourth power divider, the input terminal of the fourth power divider serves as the input terminal of the first power supply network and is connected to the first power supply point; The fifth power divider has its first output terminal connected to the input terminal of the fourth power divider; the first output terminal of the fifth power divider serves as the output terminal of the first power supply network and is connected to the first second patch; the second output terminal of the fifth power divider serves as the output terminal of the first power supply network and is connected to the second second patch. The sixth power divider has its second output terminal connected to the input terminal of the fourth power divider; the first output terminal of the sixth power divider serves as the output terminal of the first power supply network and is connected to the third second patch; the second output terminal of the sixth power divider serves as the output terminal of the first power supply network and is connected to the fourth second patch. A 1 / 4 wavelength transmission line is provided between the second output terminal of the fourth power divider and the input terminal of the sixth power divider, between the second output terminal of the fifth power divider and the second second patch, and between the second output terminal of the sixth power divider and the fourth second patch.

9. The dual-frequency dual-circular polarization antenna array as described in claim 8, characterized in that, The first power divider, the second power divider, and the third power divider are all T-type power dividers or Wilkinson power dividers; and / or, the fourth power divider, the fifth power divider, and the sixth power divider are all T-type power dividers or Wilkinson power dividers.

10. The dual-frequency dual-circular polarization antenna array as described in claim 1, characterized in that, The output of the first power supply network is fed to multiple first patches via a slot plate or coaxial cable, and the output of the second power supply network is fed to multiple second patches via a slot plate or coaxial cable.

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