Dual-polarized antenna with adjustable radiated null point for use in satellite communication phased array systems

Abstract

This invention discloses a dual-polarized antenna with tunable radiated null point for use in a satellite communication phased array system. It includes an RF connector, a radiating metal patch, a metal ground plane, and a dielectric substrate located between the radiating metal patch and the metal ground plane. The radiating metal patch comprises four sets of metal plates, with any two adjacent sets spaced apart. There are four sets of RF connectors, each connecting to one set of metal plates. The dual-polarized antenna also includes two sets of radiated null point scanning control networks. One set connects to two opposing sets of metal plates via RF connectors, and the other set connects to two other opposing sets of metal plates via RF connectors. This invention's dual-polarized antenna with tunable radiated null point has a simple structure and can achieve scanning control and dual polarization of the radiated null point.

Description

Technical Field

[0001] The present invention relates to the field of antenna technology, and in particular to a dual-polarized antenna with adjustable radiating null point for use in a phased array system for satellite communication. Background Technology

[0002] In high-performance applications such as satellite communications, antenna arrays employing large element spacing exceeding half a wavelength can lead to severe grating lobe problems, essentially resulting in aliasing during spatial sampling. The core impact of this issue lies in its dispersion of radiated energy, thus reducing the main beam gain. More seriously, these grating lobes, with gains similar to the main beam, generate strong undesirable radiation, causing not only co-channel interference to other receiving devices but also security risks such as interception and attack. Furthermore, it leads to beam orientation misalignment and angular ambiguity, compromising spatial multiplexing capabilities, ultimately resulting in a significant decline in the overall system's communication quality, security, and capacity. Therefore, actively researching and implementing effective grating lobe suppression is crucial for unlocking the full performance potential of antenna arrays and ensuring the reliability and security of communication links.

[0003] To achieve grating lobe suppression in large-cell-pitch arrays, the main technical approaches are array factor optimization and cell pattern zero-scanning. Cell pattern zero-scanning adds new degrees of freedom for grating lobe suppression optimization, and when combined with array factor optimization schemes, it can achieve better grating lobe suppression results.

[0004] To achieve null scanning of the element pattern, various implementation methods have been proposed. The paper "Null-Reconfigurable Patch Antenna Scheme and Design Based on Multimode Method" published in Volume 71, Issue 8, pp. 6286-6296 of the *IEEE Transactions on Antennas and Propagations* describes a method that simultaneously excites multiple modes of a single radiator at the same operating frequency. By adjusting the phase difference and excitation ratio between modes at different feed point positions, the radiation null of the element pattern can be achieved at different angles. However, this design requires the introduction of lumped capacitance in the feed network layer to control antenna matching, and also requires the use of multiple pins to switch feed positions, increasing the design complexity of the feed network layer and preventing dual polarization. The paper "Enhanced Isolation Hybrid Mode Element-Level Beamforming Antenna for Phased Array Applications" published in Volume 72, Issue 5, pp. 4577-4582 of the IEEE Transactions on Antennas and Propagations introduces a hybrid mode element-level beamforming antenna suitable for large element spacing arrays. This antenna can achieve scanning control of the radiation null point by finely adjusting the amplitude and phase of the signals of each element. However, the structure of this antenna element is relatively complex, requiring multiple structures to be independently fabricated and assembled, and dual polarization cannot be achieved. Summary of the Invention

[0005] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a dual-polarized antenna with adjustable radiation null point for use in satellite communication phased array systems. It has a simple structure and can achieve scanning control and dual polarization of the radiation null point.

[0006] According to a first aspect of the present invention, a radiated null-tunable dual-polarized antenna for a satellite communication phased array system includes an RF connector, a radiating metal patch, a metal ground plane, and a dielectric substrate located between the radiating metal patch and the metal ground plane.

[0007] An XY coordinate system is established with the geometric center of the radiating metal patch as the origin, and the system is divided into a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant. The X-axis is parallel to one side of the radiating metal patch, and the Y-axis is parallel to the other adjacent side of the radiating metal patch. The radiating metal patch includes four sets of metal sheets, which are respectively disposed in the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant, and any two adjacent sets of metal sheets are spaced apart.

[0008] The number of radio frequency connectors is four sets, and each radio frequency connector is connected to one set of metal plates;

[0009] The tunable null-point dual-polarized antenna further includes two sets of null-point scanning control networks. One set of the null-point scanning control networks is connected to the metal sheet in the first quadrant and the metal sheet in the third quadrant via the radio frequency connector. The other set of the null-point scanning control networks is connected to the metal sheet in the second quadrant and the metal sheet in the fourth quadrant via the radio frequency connector.

[0010] Each of the radiation null-scan control networks includes a power divider and a phase shifter. The power divider is used to generate a first signal and a second signal with equal amplitude and in phase. The phase shifter is used to receive the second signal and adjust the phase of the second signal to generate a third signal.

[0011] Among them, one of the metal sheet in the first quadrant and the metal sheet in the third quadrant receives a first signal from a group of radiation zero-point scanning control networks, and the other receives a third signal from the same group of radiation zero-point scanning control networks, and together they generate a first linearly polarized electromagnetic wave.

[0012] One of the metal sheet in the second quadrant and the metal sheet in the fourth quadrant receives a first signal from another set of the radiation zero-point scanning control network, and the other receives a third signal from the same set of the radiation zero-point scanning control network, and together they generate a second linearly polarized electromagnetic wave orthogonal to the first linearly polarized electromagnetic wave.

[0013] The dual-polarized antenna with adjustable radiation null point applied to a satellite communication phased array system according to embodiments of the present invention has at least the following beneficial effects:

[0014] A power divider is used to generate a first signal and a second signal with equal amplitude and phase. A phase shifter is used to adjust the phase of the second signal to generate a third signal. The third signal and the first signal have the same amplitude but different phases. The phase difference between the first signal and the third signal can be flexibly controlled by the phase shifter. One of the metal plates in the first quadrant and the metal plate in the third quadrant receives a first signal from a radiation null scan control network, and the other receives a third signal from the same radiation null scan control network. Together, they generate a first linearly polarized electromagnetic wave. One of the metal plates in the second quadrant and the metal plate in the fourth quadrant receives a first signal from another radiation null scan control network, and the other receives a third signal from the same radiation null scan control network. Together, they generate a second linearly polarized electromagnetic wave orthogonal to the first linearly polarized electromagnetic wave, thus achieving a dual-polarization layout. At the same time, the phase of the second signal is continuously adjusted by a phase shifter to obtain different phase differences between the first and third signals. This allows for the control of the excitation ratio and phase difference of the differential-mode and common-mode signals, thereby achieving radiation nulls at different radiation angles. In this way, the phase shifter in the radiation null scan control network achieves scanning control of the antenna pattern radiation null.

[0015] According to some embodiments of the present invention, the metal sheet in the first quadrant and the metal sheet in the third quadrant are symmetrically arranged on both sides of a straight line passing through the origin and equally dividing the second quadrant.

[0016] The metal sheet in the second quadrant and the metal sheet in the fourth quadrant are symmetrically arranged on both sides of a straight line passing through the origin and equally dividing the first quadrant.

[0017] According to some embodiments of the present invention, a plurality of electromagnetic shielding structures are further provided, respectively disposed between adjacent metal sheets extending along the X-axis or between adjacent metal sheets extending along the Y-axis, and spaced apart from the metal sheets. The electromagnetic shielding structures are used to improve the isolation between the first linearly polarized electromagnetic wave and the second linearly polarized electromagnetic wave.

[0018] According to some embodiments of the present invention, the electromagnetic shielding structure includes a metal via array and a connected metal patch. The metal via array includes a plurality of metallized vias spaced apart along the X-axis or along the Y-axis. One end of the plurality of metallized vias is connected to the connected metal patch, the metallized vias pass through the dielectric substrate, and the other end of the plurality of metallized vias is connected to the metal ground plate.

[0019] According to some embodiments of the present invention, the radiation null-adjustable dual-polarized antenna further includes a plurality of short-circuit metallized vias, the short-circuit metallized vias being correspondingly disposed with the metal sheets, wherein each of the metal sheets has a closed annular slit, the annular slit dividing the metal sheet into a first metal part and a second metal part, the first metal part being located inside the annular slit, and the second metal part being located outside the annular slit. The radiation null-adjustable dual-polarized antenna further includes a circular patch, the circular patch being connected to the second metal part, one end of the short-circuit metallized via being connected to the circular patch and the central axis of the short-circuit metallized via passing through the center of the circular patch, the short-circuit metallized via passing through the dielectric substrate, and the other end of the short-circuit metallized via being connected to the metal ground plane.

[0020] According to some embodiments of the present invention, the radius of the circular patch is larger than the radius of the short-circuit metallized via.

[0021] According to some embodiments of the present invention, the intersection of two adjacent sides of the metal sheet forms an intersection point, and the projection distance in the XY plane between the central axis of the short-circuit metallized through hole and the intersection point of the metal sheet near the origin is less than the projection distance in the XY plane between the center of the annular gap and the intersection point of the metal sheet near the origin.

[0022] According to some embodiments of the present invention, the radio frequency connector includes an inner conductor and an outer conductor, the inner conductor passing through the dielectric substrate and connected to the metal sheet, the outer conductor being connected to the metal ground plane, wherein each of the metal sheets has a feed point, the inner conductor being connected to the feed point, and the feed point being located at the center of the annular gap.

[0023] According to some embodiments of the present invention, two adjacent edges of the metal sheet intersect to form an intersection point; a first line connects the intersection point of the metal sheet in the first quadrant near the origin and the intersection point of the metal sheet in the third quadrant near the origin; the minimum distance between the center of the annular gap of the metal sheet in the first quadrant and the center of the annular gap of the metal sheet in the third quadrant and the first line is less than 0.02λ, where λ is the wavelength.

[0024] According to some embodiments of the present invention, two adjacent edges of the metal sheet intersect to form an intersection point;

[0025] A second line connects the intersection point of the metal sheet in the second quadrant near the origin with the intersection point of the metal sheet in the fourth quadrant near the origin. The minimum distance between the center of the annular slit in the metal sheet in the second quadrant and the center of the annular slit in the metal sheet in the fourth quadrant and the second line is less than 0.02λ, where λ is the wavelength.

[0026] According to some embodiments of the present invention, the distance between the center of the annular slit and the origin is 0.08λ-0.18λ, where λ is the wavelength.

[0027] According to some embodiments of the present invention, the ratio of the inner radius of the annular slit to the inner conductor radius of the radio frequency connector is greater than 2.

[0028] According to some embodiments of the present invention, the metal floor is provided with a plurality of circular hollow areas, each of which is provided in a one-to-one correspondence with a power supply point, and the center of the circular hollow area overlaps with the projection of the corresponding power supply point in the XY plane.

[0029] The radii of the four circular cutout areas are larger than the inner conductor radius of the RF connector.

[0030] According to some embodiments of the present invention, the metal sheet is square, and the side length of each metal sheet is greater than 0.15λ, where λ is the wavelength.

[0031] According to some embodiments of the present invention, rectangular slots are provided on the two sides of each metal sheet away from the origin, wherein the rectangular slots provided on the side extending along the Y-axis extend along the X-axis, and the rectangular slots provided on the side extending along the X-axis extend along the Y-axis.

[0032] According to some embodiments of the present invention, the width of the rectangular slit is in the range of 0.005λ-0.04λ, where λ is the wavelength.

[0033] According to some embodiments of the present invention, the distance between the width bisector of the rectangular slit extending along the X-axis and the side extending along the X-axis away from the origin ranges from 0.077λ to 0.142λ, where λ is the wavelength.

[0034] According to some embodiments of the present invention, the distance between the width bisector of the rectangular slit extending along the Y-axis and the side extending along the Y-axis away from the origin ranges from 0.077λ to 0.142λ, where λ is the wavelength.

[0035] According to some embodiments of the present invention, the thickness of the dielectric substrate is less than 0.15λ, where λ is the wavelength.

[0036] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0037] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0038] Figure 1 This is a schematic diagram of the structure of the radiating metal patch, dielectric substrate, metal ground plane, electromagnetic shielding structure, short-circuit metallized via, and circular patch of the radiating null-adjustable dual-polarized antenna according to an embodiment of the present invention.

[0039] Figure 2 This is a schematic diagram of the radiating metal patch, metal ground plane, electromagnetic shielding structure, short-circuit metallized via, and circular patch of the radiating null-adjustable dual-polarized antenna according to an embodiment of the present invention.

[0040] Figure 3 This is a schematic diagram of the radiating metal patch, electromagnetic shielding structure, and circular patch of the radiating null-adjustable dual-polarized antenna according to an embodiment of the present invention.

[0041] Figure 4 This is a schematic diagram of the radiation null-point scanning control network of the radiation null-point adjustable dual-polarized antenna according to an embodiment of the present invention.

[0042] Figure 5 This is a schematic diagram showing the relative positions of multiple components of the tunable dual-polarized antenna with a zero-radiation point according to an embodiment of the present invention.

[0043] Figure 6 The curve showing the port reflection coefficient as a function of operating frequency obtained from the simulation test of the tunable dual-polarized antenna with radiated null point according to an embodiment of the present invention.

[0044] Figure 7 The curve showing the isolation as a function of operating frequency obtained from the simulation of the tunable dual-polarized antenna with radiated null point according to an embodiment of the present invention.

[0045] Figure 8 The simulation results of the tunable dual-polarized antenna with radiated null point are shown in the E-plane radiation pattern at the operating frequency of 4.85 GHz with different phase shifts of the phase shifter.

[0046] Figure 9 The radiation null-adjustable dual-polarized antenna of this embodiment of the invention is shown in the radiation pattern at a 45° angle to the E plane when the phase shifter has different phase shifts at the operating frequency of 4.85 GHz.

[0047] Figure label:

[0048] 100. Radiation metal patch; 110. Metal sheet; 110a. Feed point; 111. Circular slit; 112. Rectangular slit; 113. First metal part; 114. Second metal part;

[0049] 200. Metal floor; 210. Circular openwork area;

[0050] 300. Dielectric substrate;

[0051] 400. Electromagnetic shielding structure; 410. Metal through-hole array; 411. Metallized through-hole; 420. Connecting metal patch;

[0052] 500, short-circuit metallized via; 600, circular surface mount;

[0053] 710. Power divider; 720. Phase shifter. Detailed Implementation

[0054] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0055] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0056] In the description of the embodiments of this application, the technical terms "first," "second," "third," etc., are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0057] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0058] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects are in an "or" relationship.

[0059] In the description of the embodiments of this application, the technical terms "top", "bottom", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed, operated or used in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0060] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0061] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical term "contact" should be interpreted broadly, and can be direct contact, contact through an intermediate medium layer, contact between two contacting parties with substantially no interaction force, or contact between two contacting parties with interaction force.

[0062] Please refer to Figures 1-9 This application provides a dual-polarized antenna with adjustable radiated null point for use in a phased array satellite communication system, including an RF connector, a radiating metal patch 100, a metal ground plane 200, and a dielectric substrate 300 located between the radiating metal patch 100 and the metal ground plane 200.

[0063] Please refer to Figure 1 The radiating metal patch 100, the metal ground plane 200, and the dielectric substrate 300 together form a radiating structure to convert electrical signals into electromagnetic wave signals. The metal ground plane 200 and the radiating metal patch 100 are separated by the dielectric substrate 300. The metal ground plane 200 is used to provide a ground reference for the radiating metal patch 100.

[0064] Please refer to Figure 3 An XY coordinate system is established with the geometric center of the radiating metal patch 100 as the origin, and the system is divided into a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant. The X-axis is parallel to one side of the radiating metal patch 100, and the Y-axis is parallel to the other adjacent side of the radiating metal patch 100. The radiating metal patch 100 includes four sets of metal plates 110, which are respectively set in the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant, and any two adjacent sets of metal plates 110 are spaced apart.

[0065] There are four sets of RF connectors, each connected to a set of metal plates 110. The RF connectors are used to feed RF signals into the corresponding metal plates 110 to excite the antenna.

[0066] Please refer to Figure 4 The tunable radiated null dual-polarized antenna also includes two sets of radiated null scanning control networks. One set of radiated null scanning control networks is connected to the metal piece 110 in the first quadrant through a set of radio frequency connectors and to the metal piece 110 in the third quadrant through a set of radio frequency connectors. The other set of radiated null scanning control networks is connected to the metal piece 110 in the second quadrant through a set of radio frequency connectors and to the metal piece 110 in the fourth quadrant through another set of radio frequency connectors.

[0067] Each set of radiation null-point scanning control networks includes a power divider 710 and a phase shifter 720. The power divider 710 generates a first signal and a second signal with equal amplitude and phase, wherein the first signal and the second signal have the same phase and equal amplitude. The power divider 710 is a 1-to-2 power divider. The phase shifter 720 receives the second signal and adjusts its phase to generate a third signal, wherein the third signal has an adjustable phase difference with the first signal.

[0068] One of the metal plates 110 in the first quadrant and the metal plate 110 in the third quadrant receives a first signal from a set of radiation null-point scanning control networks, while the other receives a third signal from the same set of radiation null-point scanning control networks, and together they generate a first linearly polarized electromagnetic wave. Specifically, the first and third signals of a set of radiation null-point scanning control networks are fed into two diagonally opposite sets of metal plates 110 through RF connectors, forming a differential-mode and common-mode superposition excitation mode. By adjusting the phase shift of the phase shifter 720, the phase difference between the two signals is changed, thereby controlling the position of the radiation null point in the antenna pattern and achieving continuous scanning of the radiation null point in the elevation direction. One of the metal plates 110 in the second quadrant and the metal plate 110 in the fourth quadrant receives a first signal from another set of radiation null-point scanning control networks, while the other receives a third signal from the same set of radiation null-point scanning control networks, and together they generate a second linearly polarized electromagnetic wave. Specifically, the first and third signals of another set of radiation null scanning control networks are also fed into two diagonally opposite sets of metal plates 110 through RF connectors, forming a differential-mode and common-mode superposition excitation mode. By adjusting the phase shift of the phase shifter 720, the phase difference between the two signals is changed, thereby controlling the position of the radiation null in the antenna pattern and realizing continuous scanning of the radiation null in the elevation direction. The second linearly polarized electromagnetic wave is orthogonal to the first linearly polarized electromagnetic wave, realizing a dual-polarization layout.

[0069] It is understood that the phase shifter 720 has one RF input port and one RF output port. One output port of the power divider 710 is connected to the RF input port of the phase shifter 720, and the other output port of the power divider 710 is connected to the RF connectors corresponding to a set of metal plates 110. The output port of the phase shifter 720 is connected to the RF connectors corresponding to another set of metal plates 110.

[0070] In the above embodiment, the power divider 710 is used to generate the same first signal and second signal, and the phase shifter 720 is used to adjust the phase of the second signal to generate a third signal, so that the third signal and the first signal have the same amplitude but different phases. One of the metal plates 110 in the first quadrant and the metal plate 110 in the third quadrant receives a first signal from a set of radiation null scan control networks, and the other receives a third signal from the same set of radiation null scan control networks, and together they generate a first linearly polarized electromagnetic wave. One of the metal plates 110 in the second quadrant and the metal plate 110 in the fourth quadrant receives a first signal from another set of radiation null scan control networks, and the other receives a third signal from the same set of radiation null scan control networks, and together they generate a second linearly polarized electromagnetic wave orthogonal to the first linearly polarized electromagnetic wave, thereby realizing a dual-polarization layout. At the same time, the phase of the second signal is continuously adjusted by the phase shifter 720 to obtain a third signal with different phases, thereby realizing the control of the excitation ratio and phase difference of the differential mode signal and the common mode signal to achieve radiation null at different radiation angles. Thus, the phase shifter in the radiation null scan control network realizes the scanning control of the radiation null of the antenna pattern.

[0071] Furthermore, the application of radiation pattern nullable antennas in satellite communication phased array systems provides a key solution to address the inherent challenges of large element spacing design (especially the grating lobe suppression problem).

[0072] According to antenna theory, when the spacing between phased array elements exceeds half a wavelength, high-intensity grating lobes or secondary beams will inevitably be generated in real or virtual space during beam scanning. These fixed-position sidelobes waste radiated energy and become uncontrollable interference sources, severely degrading system performance. By introducing tunable null-radiating antennas, the design freedom of the system is fundamentally expanded: on the one hand, during array synthesis, the radiation pattern of each independent tunable null-radiating antenna can be optimized, so that it pre-forms deep nulls in the directions where grating lobes may appear, as determined by the array layout, thereby directly suppressing the generation of these harmful grating lobes. This allows engineers to use larger tunable null-radiating antenna spacing to reduce costs, simplify the feed network, or accommodate more complex antenna structures without bearing the performance loss caused by grating lobes; on the other hand, during dynamic operation, combined with the inherent beamforming capability of the phased array, the system can achieve real-time null synthesis and tracking in all directions other than the main lobe, forming an "adaptive spatial filtering" mechanism. The significance of this technology lies in its transformation of antennas from traditional, single-characteristic radiators into "smart pixels" with specific spatial spectrum shaping capabilities. This allows phased array systems to employ more flexible (such as sparse or irregular) array topologies to improve aperture efficiency or achieve multi-band co-aperture designs, while maintaining a clean radiation pattern at all times. Therefore, the combination of null-tunable antennas with phased arrays not only enhances anti-interference capabilities but also revolutionizes the design paradigm of large-scale sparse phased arrays at the physical level, laying the technological foundation for next-generation high-throughput satellites to achieve wider scanning ranges, higher gains, and better co-location compatibility.

[0073] Please refer to Figure 3 In some embodiments, the metal sheet 110 in the first quadrant and the metal sheet 110 in the third quadrant are symmetrically arranged on both sides of a straight line passing through the origin and equally dividing the second quadrant, and the metal sheet 110 in the second quadrant and the metal sheet 110 in the fourth quadrant are symmetrically arranged on both sides of a straight line passing through the origin and equally dividing the first quadrant.

[0074] Metal plates 110 in the first quadrant and the fourth quadrant are symmetrically arranged on both sides of the X-axis. Similarly, metal plates 110 in the second quadrant and the third quadrant are symmetrically arranged on both sides of the X-axis. Metal plates 110 in the first quadrant and the second quadrant are symmetrically arranged on both sides of the Y-axis. Similarly, metal plates 110 in the third quadrant and the fourth quadrant are also symmetrically arranged on both sides of the Y-axis, ensuring the symmetry and independence of the bilinear polarization excitation.

[0075] Please refer to Figure 2 and Figure 3In some embodiments, the tunable dual-polarized antenna further includes multiple electromagnetic shielding structures 400, respectively disposed between adjacent metal sheets 110 extending along the X-axis or between adjacent metal sheets 110 extending along the Y-axis, that is, between metal sheets 110 in the first quadrant and metal sheets 110 in the second quadrant, between metal sheets 110 in the second quadrant and metal sheets 110 in the third quadrant and metal sheets 110 in the fourth quadrant, and between metal sheets 110 in the fourth quadrant and metal sheets 110 in the first quadrant. The electromagnetic shielding structures 400 are spaced apart from the metal sheets 110. The electromagnetic shielding structures 400 regulate the electromagnetic field between the first linearly polarized electromagnetic wave and the second linearly polarized electromagnetic wave, thereby improving the isolation between the first linearly polarized electromagnetic wave and the second linearly polarized electromagnetic wave. For example, the isolation between the first linearly polarized electromagnetic wave and the second linearly polarized electromagnetic wave is greater than 17 dB.

[0076] Please refer to Figure 2 In some embodiments, the electromagnetic shielding structure 400 includes a metal via array 410 and a connected metal patch 420. The metal via array 410 includes a plurality of metallized vias 411 spaced apart along the X-axis or along the Y-axis. It is understood that the electromagnetic shielding structure 400 disposed between the metal patches 110 in the first quadrant and the metal patches 110 in the second quadrant, and between the metal patches 110 in the third quadrant and the metal patches 110 in the fourth quadrant, is arranged with the metal via array 410 along the Y-axis, while the electromagnetic shielding structure 400 disposed between the metal patches 110 in the second quadrant and the metal patches 110 in the third quadrant, and between the metal patches 110 in the fourth quadrant and the metal patches 110 in the first quadrant, is arranged with the metal via array 410 along the X-axis.

[0077] Multiple metallized vias 411 are connected at one end to a metal patch 420 and pass through a dielectric substrate 300. The other end of the multiple metallized vias 411 is connected to a metal ground plane 200. The multiple metallized vias 411 are arranged in parallel.

[0078] For example, the electromagnetic shielding structure 400 is located between adjacent metal sheets 110 and is equidistant from them. The length of the electromagnetic shielding structure 400 is 0.14λ, and the distance between the electromagnetic shielding structure 400 and the origin of the coordinate system is 0.155λ, where λ is the wavelength, which refers to the wavelength in free space. For example, λ is the wavelength at a frequency of 4.85 GHz.

[0079] Please refer to Figure 2 and Figure 3In some embodiments, the radiation null-adjustable dual-polarized antenna further includes multiple short-circuit metallized vias 500, which are arranged one-to-one with the metal sheets 110. Each metal sheet 110 has a closed annular slit 111, and the feed point 110a is located at the center of the annular slit 111. The annular slit 111 divides the metal sheet 110 into a first metal part 113 and a second metal part 114. The first metal part 113 is located inside the annular slit 111, and the second metal part 114 is located outside the annular slit 111.

[0080] The radiating null-adjustable dual-polarized antenna also includes a circular patch 600, which is connected to a second metal part 114. The two parts overlap at least partially along the thickness direction. One end of a short-circuit metallized via 500 is connected to the circular patch 600. The central axis of the short-circuit metallized via 500 passes through the center of the circular patch 600. The short-circuit metallized via 500 is disposed in the dielectric substrate 300. The other end of the short-circuit metallized via 500 is connected to the metal ground plane 200.

[0081] In some embodiments, the radius of the circular patch 600 is larger than the radius of the short-circuit metallized via 500.

[0082] Please refer to Figure 3 In some embodiments, the intersection of two adjacent sides of the metal sheet 110 forms an intersection point. The projection distance in the XY plane between the central axis of the short-circuit metallized through hole 500 and the intersection point of the metal sheet 110 near the origin is less than the projection distance in the XY plane between the center of the annular gap 111 and the intersection point of the metal sheet 110 near the origin.

[0083] In some embodiments, the radio frequency connector includes an inner conductor and an outer conductor. The inner conductor passes through the dielectric substrate 300 and is connected to a metal sheet 110, while the outer conductor is connected to a metal ground plane 200. Each metal sheet 110 has a feed point 110a, and the inner conductor is connected to the feed point 110a.

[0084] Please refer to Figure 2 and Figure 3 Each metal sheet 110 has a closed annular gap 111, and the feed point 110a is located at the center of the annular gap 111 to compensate for the inductive reactance caused by the introduction of the short-circuit metallized via 500, so as to achieve a good impedance matching effect.

[0085] Please refer to Figure 3In some embodiments, two adjacent sides of the metal sheet 110 intersect to form an intersection point. For a square metal sheet 110, there are four intersection points. The intersection point of the metal sheet 110 in the first quadrant near the origin and the intersection point of the metal sheet 110 in the third quadrant near the origin are connected by a first line. The minimum distance between the center of the annular gap 111 in the first quadrant and the center of the annular gap 111 in the third quadrant and the first line is less than 0.02λ, where λ is the wavelength, so as to ensure the polarization purity of the radiated electromagnetic wave.

[0086] In some embodiments, a second line connects the intersection point of the metal sheet 110 in the second quadrant near the origin with the intersection point of the metal sheet 110 in the fourth quadrant near the origin. The minimum distance between the center of the annular slit 111 in the second quadrant and the center of the annular slit 111 in the fourth quadrant and the second line is less than 0.02λ, where λ is the wavelength.

[0087] In some embodiments, the distance between the center of the annular slit 111 and the origin is 0.08λ-0.18λ. If the distance exceeds this range, the real part of the antenna's input impedance will be too large or too small, affecting the antenna's matching.

[0088] In some embodiments, the ratio of the inner radius of the annular slit 111 to the inner conductor radius of the RF connector is greater than 2.

[0089] In some embodiments, the metal floor 200 is provided with multiple circular cutout areas 210, each corresponding to a circular annular gap 111. The center of the circular cutout area 210 and the center of the corresponding circular annular gap 111 are projected onto the XY plane. The circular cutout area 210 and the feed point 110a are also provided, each corresponding to the feed point 110a. The center of the circular cutout area 210 and the feed point 110a are projected onto the XY plane. The radius of the four circular cutout areas 210 is larger than the inner conductor radius of the RF connector.

[0090] In some embodiments, the metal sheet 110 is square, and the side length of each metal sheet 110 is greater than 0.15λ, where λ is the wavelength. The side length of the radiating metal patch 100 is greater than 0.4λ, and the side length of the radiating metal patch 100 is the sum of the side lengths of the two sets of metal sheets 110 in the same direction and the length of the interval between the two sets of metal sheets 110.

[0091] In some embodiments, rectangular slots 112 are provided on the two sides of each metal sheet 110 away from the origin. One of these two sides extends along the Y-axis, and the other extends along the X-axis. The rectangular slot 112 on the side extending along the Y-axis extends along the X-axis, and the rectangular slot 112 on the side extending along the X-axis extends along the Y-axis. These rectangular slots 112 are used to control the common-mode resonant frequency, enabling a reduction in the size of the metal sheet without affecting radiation performance.

[0092] Furthermore, in some embodiments, the width of the rectangular slit 112 ranges from 0.005λ to 0.04λ.

[0093] In some embodiments, the distance between the width bisector of the rectangular slit 112 extending along the X-axis and the side extending away from the origin along the X-axis ranges from 0.077λ to 0.142λ.

[0094] In some embodiments, the distance between the width bisector of the rectangular slit 112 extending along the Y-axis and the side extending away from the origin along the Y-axis ranges from 0.077λ to 0.142λ.

[0095] In some embodiments, the dielectric substrate 300 has a thickness of less than 0.15λ, where λ is the wavelength, to achieve low profile characteristics of the antenna.

[0096] This application provides a specific embodiment and, in conjunction with its simulation, provides a detailed description of the application effects of the present invention.

[0097] Please refer to Figure 5In this embodiment, the radiated null-adjustable dual-polarized antenna includes an RF connector, a radiating metal patch 100, a metal ground plane 200, and a dielectric substrate 300 located between the radiating metal patch 100 and the metal ground plane 200. The radiating metal patch 100 is square. An XY coordinate system is established with the geometric center of the radiating metal patch 100 as the origin, one side of the radiating metal patch 100 as the X-axis, and the adjacent side of the radiating metal patch 100 as the Y-axis. The system is divided into four quadrants: the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant. The radiating metal patch 100 includes four sets of metal plates 110, which are respectively set in the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant. Any two adjacent sets of metal plates 110 are spaced apart. Each set of metal plates 110 is square. The metal plates 110 in the first quadrant and the metal plates 110 in the third quadrant are symmetrically set on both sides of a straight line passing through the origin and equally bisecting the second quadrant. The metal plates 110 in the second quadrant and the metal plates 110 in the fourth quadrant are symmetrically set on both sides of a straight line passing through the origin and equally bisecting the first quadrant. Metal sheets 110 in the first quadrant and the fourth quadrant are symmetrically arranged on both sides of the X-axis. Similarly, metal sheets 110 in the second quadrant and the third quadrant are symmetrically arranged on both sides of the X-axis. Metal sheets 110 in the first quadrant and the second quadrant are symmetrically arranged on both sides of the Y-axis. Similarly, metal sheets 110 in the third quadrant and the fourth quadrant are also symmetrically arranged on both sides of the Y-axis.

[0098] The radiating metal patch 100, the metal ground plane 200, and the dielectric substrate 300 form a square structure with an overall side length of 0.97λ and a thickness of 0.066λ, where λ is the wavelength at 4.85 GHz. The radiating metal patch 100 is square with a side length A5 of 0.46λ. The spacing A6 between adjacent metal patches 110 is 0.065λ, and the dielectric constant of the dielectric substrate 300 is 4.4.

[0099] The tunable dual-polarized antenna also includes multiple electromagnetic shielding structures 400, which are respectively disposed between adjacent metal plates 110 along the X-axis or between adjacent metal plates 110 along the Y-axis, and spaced apart from the metal plates 110. Each electromagnetic shielding structure 400 includes a metal via array 410 and a connecting metal patch 420. The metal via array 410 includes multiple metallized vias 411 spaced apart along the X-axis or Y-axis. One end of each metallized via 411 is connected to the connecting metal patch 420, and the metallized vias 411 pass through the dielectric substrate 300. The other end of each metallized via 411 is connected to a metal ground plane 200. The length A3 of the electromagnetic shielding structure 400 is 0.142λ, and the interval A8 between the electromagnetic shielding structure 400 and the origin is 0.155λ.

[0100] Each metal sheet 110 has a rectangular slit 112 on each of its two sides away from the origin. The length A2 of the rectangular slit 112 is 0.065λ, and the width A1 is 0.016λ. The distance A4 between the bisector of the rectangular slit 112 extending along the X-axis and the side of the metal sheet 110 extending along the X-axis away from the origin is 0.11λ. The distance A11 between the bisector of the rectangular slit 112 extending along the Y-axis and the side of the metal sheet 110 extending along the Y-axis away from the origin is also 0.11λ. Each metal sheet 110 also has a closed annular slit 111. The inner diameter A9 of the annular slit 111 is 0.032λ, the outer diameter A10 is 0.04λ, and the distance A7 between the center of the annular slit 111 and the origin is 0.114λ.

[0101] 1. Simulation Content

[0102] Please refer to Figures 6 to 9 The reflection coefficient, isolation, phase shift of the phase shifter at 4.85 GHz on the E-plane and the antenna pattern and gain at a 45° angle to the E-plane were simulated using simulation software.

[0103] 2. Simulation Results

[0104] Figure 6 This is a curve showing the port reflection coefficient as a function of operating frequency, obtained from antenna simulation tests of the embodiment. It can be seen that the reflection coefficients of both common-mode and differential-mode modes in the 4.8GHz-4.9GHz frequency band are below -10dB.

[0105] Figure 7 This is a curve showing the isolation as a function of operating frequency, obtained from antenna simulation of the embodiment. It can be seen that the isolation can exceed 17dB when both linear polarizations are operating in common mode and differential mode.

[0106] Figure 8 This is the E-plane radiation pattern obtained from the antenna simulation of the embodiment at the operating frequency of 4.85 GHz with different phase shifts of the phase shifter. It can be seen that by adjusting the phase shift of the phase shifter, the angle of the corresponding polarization pattern radiation null point can be controlled. This can be used in phased arrays such as satellite communication with large element spacing to suppress grating lobes and improve anti-interference capability.

[0107] Figure 9 The image shows the radiation pattern at a 45° angle to the E-plane, obtained from antenna simulation of the embodiment at the operating frequency of 4.85 GHz with different phase shifts of the phase shifter. It can be seen that good radiation null point control can be achieved even at a 45° angle to the E-plane, and grating lobes can be suppressed in a ±45° polarization array system.

[0108] The above embodiments are merely illustrative of the technical solutions of this application and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application, and all should be covered within the scope of the specification of this application. In particular, as long as there is no structural conflict, the various technical features mentioned in the embodiments can be combined in any way. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of protection.

Claims

1. A dual-polarized antenna with adjustable radiated null point for use in satellite communication phased array systems, characterized in that, It includes an RF connector, a radiating metal patch, a metal ground plane, and a dielectric substrate located between the radiating metal patch and the metal ground plane; An XY coordinate system is established with the geometric center of the radiating metal patch as the origin, and the system is divided into a first quadrant, a second quadrant, a third quadrant, and a fourth quadrant. The X-axis is parallel to one side of the radiating metal patch, and the Y-axis is parallel to the other adjacent side of the radiating metal patch. The radiating metal patch includes four sets of metal sheets, which are respectively disposed in the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant, and any two adjacent sets of metal sheets are spaced apart. The number of radio frequency connectors is four sets, and each radio frequency connector is connected to one set of metal plates; The tunable null-point dual-polarized antenna further includes two sets of null-point scanning control networks. One set of the null-point scanning control networks is connected to the metal sheet in the first quadrant and the metal sheet in the third quadrant via the radio frequency connector. The other set of the null-point scanning control networks is connected to the metal sheet in the second quadrant and the metal sheet in the fourth quadrant via the radio frequency connector. Each of the radiation null-scan control networks includes a power divider and a phase shifter. The power divider is used to generate a first signal and a second signal with equal amplitude and in phase. The phase shifter is used to receive the second signal and adjust the phase of the second signal to generate a third signal. Among them, one of the metal sheet in the first quadrant and the metal sheet in the third quadrant receives a first signal from a group of radiation zero-point scanning control networks, and the other receives a third signal from the same group of radiation zero-point scanning control networks, and together they generate a first linearly polarized electromagnetic wave. One of the metal sheet in the second quadrant and the metal sheet in the fourth quadrant receives a first signal from another set of the radiation zero-point scanning control network, and the other receives a third signal from the same set of the radiation zero-point scanning control network, and together they generate a second linearly polarized electromagnetic wave orthogonal to the first linearly polarized electromagnetic wave. It also includes multiple electromagnetic shielding structures, which are respectively disposed between adjacent metal sheets along the X-axis extension direction or between adjacent metal sheets along the Y-axis extension direction, and are spaced apart from the metal sheets. The electromagnetic shielding structures are used to improve the isolation between the first linearly polarized electromagnetic wave and the second linearly polarized electromagnetic wave. The electromagnetic shielding structure includes a metal via array and a connected metal patch. The metal via array includes multiple metallized vias spaced apart along the X-axis or along the Y-axis. One end of each metallized via is connected to the connected metal patch, the metallized vias pass through the dielectric substrate, and the other end of each metallized via is connected to the metal ground plate. The tunable dual-polarized antenna with a radiation null point also includes multiple short-circuit metallized vias, which are correspondingly arranged with the metal sheets. Each metal sheet has a closed annular slit, which divides the metal sheet into a first metal part and a second metal part. The first metal part is located inside the annular slit, and the second metal part is located outside the annular slit. The radiated null-adjustable dual-polarized antenna further includes a circular patch connected to the second metal part. One end of the short-circuit metallized via is connected to the circular patch, and the central axis of the short-circuit metallized via passes through the center of the circular patch. The short-circuit metallized via passes through the dielectric substrate, and the other end of the short-circuit metallized via is connected to the metal ground plane.

2. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 1, characterized in that, The metal sheet in the first quadrant and the metal sheet in the third quadrant are symmetrically arranged on both sides of a straight line passing through the origin and equally dividing the second quadrant. The metal sheet in the second quadrant and the metal sheet in the fourth quadrant are symmetrically arranged on both sides of a straight line passing through the origin and equally dividing the first quadrant.

3. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 1, characterized in that, The radius of the circular patch is larger than the radius of the short-circuit metallized via; And / or, The intersection point is formed by the intersection of two adjacent sides of the metal sheet. The projection distance in the XY plane between the central axis of the short-circuit metallized through hole and the intersection point of the metal sheet near the origin is smaller than the projection distance in the XY plane between the center of the annular gap and the intersection point of the metal sheet near the origin.

4. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 1, characterized in that, The RF connector includes an inner conductor and an outer conductor. The inner conductor passes through the dielectric substrate and is connected to the metal sheet. The outer conductor is connected to the metal ground plane. Each of the metal sheets has a feed point. The inner conductor is connected to the feed point, and the feed point is located at the center of the annular gap.

5. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 4, characterized in that, The two adjacent sides of the metal sheet intersect to form an intersection point; A first line connects the intersection point of the metal sheet in the first quadrant near the origin with the intersection point of the metal sheet in the third quadrant near the origin. The minimum distance between the center of the annular gap of the metal sheet in the first quadrant and the center of the annular gap of the metal sheet in the third quadrant and the first line is less than 0.02λ, where λ is the wavelength. And / or, A second line connects the intersection point of the metal sheet in the second quadrant near the origin with the intersection point of the metal sheet in the fourth quadrant near the origin. The minimum distance between the center of the annular slit in the metal sheet in the second quadrant and the center of the annular slit in the metal sheet in the fourth quadrant and the second line is less than 0.02λ, where λ is the wavelength. And / or, The distance between the center of the annular slit and the origin is 0.08λ-0.18λ, where λ is the wavelength; And / or, The ratio of the inner radius of the annular slit to the inner conductor radius of the RF connector is greater than 2.

6. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 4, characterized in that, The metal floor has multiple circular hollow areas, each corresponding to a power supply point. The center of each circular hollow area overlaps with the projection of the corresponding power supply point in the XY plane. The radii of the four circular cutout areas are larger than the inner conductor radius of the RF connector.

7. The dual-polarized antenna with adjustable radiating null point for use in a satellite communication phased array system according to claim 1, characterized in that, The metal sheet is square, and the side length of each metal sheet is greater than 0.15λ, where λ is the wavelength.

8. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 7, characterized in that, Each of the metal sheets has a rectangular slit on two sides away from the origin. The rectangular slit on the side extending along the Y-axis extends along the X-axis, and the rectangular slit on the side extending along the X-axis extends along the Y-axis.

9. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 8, characterized in that, The width of the rectangular slit ranges from 0.005λ to 0.04λ, where λ is the wavelength. And / or, The distance between the width bisector of the rectangular slit extending along the X-axis and the side extending along the X-axis away from the origin ranges from 0.077λ to 0.142λ, where λ is the wavelength; And / or, The distance between the width bisector of the rectangular slit extending along the Y-axis and the side extending away from the origin and along the Y-axis ranges from 0.077λ to 0.142λ, where λ is the wavelength.

10. The dual-polarized antenna with adjustable radiated null point for use in a satellite communication phased array system according to claim 1, characterized in that, The thickness of the dielectric substrate is less than 0.15λ, where λ is the wavelength.

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