Antenna unit, phased array antenna and antenna module

Abstract

The application relates to the technical field of antenna communication, and discloses an antenna unit, a phased array antenna and an antenna module, which are applied to the phased array antenna and comprise a base structure. The antenna unit comprises: a groove structure arranged on a radiation patch structure; and a parasitic patch structure arranged on one side of the radiation patch structure; the parasitic patch structure is arranged in a spaced mode with the radiation patch structure, and the parasitic patch structure is used for expanding the working bandwidth of the antenna unit; wherein the radiation patch structure, the groove structure and the parasitic patch structure are coplanarly arranged on the same side surface of the base structure to form a single-layer radiation structure, and the single-layer radiation structure is used for receiving and emitting millimeter waves. The beneficial effects are that all the structures are integrated in a single-layer metal structure, the performance requirements of circular polarization, low profile and wide bandwidth can be simultaneously met on a thin flexible dielectric substrate, excellent radiation characteristics can be realized without a multi-layer stacking architecture, and the integrated requirement of a flexible phased array is met.

Description

Technical Field

[0001] This application relates to the field of antenna communication technology, and in particular to an antenna element, a phased array antenna, and an antenna module. Background Technology

[0002] The high path loss in the millimeter-wave band severely restricts communication transmission distance, and phased array technology has become a core and feasible solution to this bottleneck. With the continuous maturation of silicon-based radio frequency integrated circuits (RFICs) and printed circuit boards (PCBs), several low-cost, high-efficiency integrated millimeter-wave phased arrays have been successfully developed and are widely used in wireless communication and radar fields.

[0003] However, millimeter-wave antenna elements in related technologies struggle to balance broadband radiation characteristics and low-profile design on thin substrates, and their adaptability to flexible circuit integration is insufficient. Further improvements are needed to enhance their overall performance and integration adaptability in flexible scenarios. Summary of the Invention

[0004] This application aims to at least partially solve one of the technical problems in related technologies. To this end, this application proposes an antenna element, a phased array antenna, and an antenna module. The main technical solutions adopted in this application include: In a first aspect, this application provides an antenna element for use in a phased array antenna, the phased array antenna including a substrate structure; the antenna element includes: a radiating patch structure; a groove structure disposed on the radiating patch structure; and a parasitic patch structure disposed on one side of the radiating patch structure; the parasitic patch structure and the radiating patch structure are arranged at intervals, the parasitic patch structure being used to extend the operating bandwidth of the antenna element; wherein the radiating patch structure, the groove structure, and the parasitic patch structure are coplanarly disposed on the same side surface of the substrate structure to form a single-layer radiating structure, the single-layer radiating structure being used to receive and transmit millimeter waves.

[0005] The system utilizes a radiating patch structure to provide basic millimeter-wave radiation capability, a groove structure to simultaneously achieve polarization and resonant frequency control, and a parasitic patch structure with gaps to expand the operating bandwidth. All three are coplanarly integrated within a single-layer metal structure, which can simultaneously meet the performance requirements of circular polarization, low profile, and wide bandwidth on a thin, flexible dielectric substrate. It achieves excellent radiation characteristics without the need for a multi-layer stacked architecture, making it suitable for the integrated requirements of flexible phased arrays.

[0006] Optionally, the groove structure is disposed at a preset groove position of the radiating patch structure; the preset groove position includes a first groove position and a second groove position; the groove structure includes: a first groove structure disposed at the first groove position; wherein the first groove structure is used to realize the circular polarization radiation characteristics of the antenna element; and a second groove structure disposed at the second groove position; wherein the second groove structure is used to reduce the operating frequency of the antenna element.

[0007] This method, which involves arranging two types of groove structures with different functions at preset positions, can simultaneously achieve polarization and frequency control on the same radiating patch without adding additional structural layers, thus meeting the design requirements of circular polarization and low profile on a thin substrate.

[0008] Optionally, the first groove structure includes a first preset number of rectangular grooves, the first preset number being an even number, and the rectangular grooves are symmetrically arranged with respect to the axis of the radiating patch structure.

[0009] By employing an even number of rectangular slots symmetrically arranged along the axis, the amplitude consistency of the two sets of orthogonal modes can be guaranteed, improving the purity of circular polarization. Furthermore, the symmetrical structure avoids antenna pattern distortion, maintaining the symmetry of radiation characteristics. The rectangular slot shape also facilitates precise control of the current path length, making it easier to match dual resonant modes that meet the phase difference requirements.

[0010] Optionally, the second groove structure is a circular groove; the position of the second groove is the geometric center of the radial patch structure.

[0011] Placing the circular slot at the geometric center of the radiating patch serves two purposes: firstly, the centrally symmetrical shape does not disrupt the orthogonal mode symmetry formed by the first groove structure, ensuring that the circular polarization performance is unaffected; secondly, a single central slot can achieve full-domain current path elongation, resulting in high frequency reduction efficiency, and the circular slot provides uniform stress distribution, making it less prone to structural cracking under bending conditions.

[0012] Optionally, the parasitic patch structure includes a second preset number of parasitic branches, the second preset number being an even number, and the parasitic branches are symmetrically arranged around the geometric center of the radiating patch structure.

[0013] By employing an even number of parasitic stubs symmetrically arranged around the perimeter, consistent coupling strength in all directions can be ensured, preventing tilting and distortion of the radiation pattern. Furthermore, parasitic coupling can further widen the bandwidth coverage and improve frequency offset tolerance under bending conditions.

[0014] Secondly, this application provides a phased array antenna, which includes: a substrate structure; wherein the substrate structure includes multiple layers of flexible dielectric substrates stacked sequentially; and adjacent flexible dielectric substrates are bonded together by a flexible adhesive layer; a circuit structure located on the surface of the flexible dielectric substrate; wherein the circuit structure includes a first circuit layer located on the top layer of the substrate structure; the first circuit layer includes at least one of the above-mentioned antenna elements for radiating and receiving millimeter-wave signals, thereby forming a phased array radiation array.

[0015] The integrated architecture, which uses a multi-layer flexible dielectric substrate stacked and bonded together, integrates the antenna radiating element, RF feed, digital control and parallel power supply circuits into the same flexible substrate. Combined with the shielding design of double-layer metal ground, it effectively overcomes the problems of insufficient radiation performance and interlayer crosstalk of thin flexible substrates while ensuring flexible, bendable and conformal characteristics, and realizes a high degree of integration and high performance integrated design of millimeter wave phased array.

[0016] Optionally, the flexible dielectric substrate can be prepared from polyimide or liquid crystal polymer.

[0017] Using the two materials mentioned above to prepare flexible dielectric substrates can ensure the flexibility and bendability of the substrate while also taking into account the high-frequency transmission performance in the millimeter-wave band.

[0018] Optionally, the substrate structure, from bottom to top, includes a first flexible dielectric substrate, a first flexible adhesive layer, a second flexible dielectric substrate, a second flexible adhesive layer, a third flexible dielectric substrate, a third flexible adhesive layer, and a fourth flexible dielectric substrate stacked sequentially; a first circuit layer is located on the upper surface of the fourth flexible dielectric substrate; the circuit structure further includes: a second circuit layer located on the lower surface of the first flexible dielectric substrate, the second circuit layer being provided with a phased array chip and an external connector; the external connector is used to realize interaction with external signals; a third circuit layer located on the upper surface of the first flexible dielectric substrate, the third circuit layer being provided with a first metal ground structure; the first metal ground structure is used to realize interlayer shielding and isolation; a fourth circuit layer located on the upper surface of the second flexible dielectric substrate, the fourth circuit layer being provided with a numerical control circuit; the numerical control circuit is used to realize control signal distribution; a fifth circuit layer located on the lower surface of the third flexible dielectric substrate, the fifth circuit layer being provided with a second metal ground structure; the second metal ground structure is used to realize suppression of interlayer signal crosstalk.

[0019] By centralizing the core functional circuits on the second, fourth, and first circuit layers, and setting the third and fifth circuit layers as complete metal ground layers, all functions of radiation, power supply, control, power supply, and shielding isolation can be achieved simultaneously within a five-layer circuit architecture. This simplifies the total number of substrate layers, reduces the processing difficulty and bending / delamination risk of multilayer flexible boards, and effectively suppresses interlayer signal crosstalk through the double-layer metal ground structure, thus balancing flexible process adaptability and high-frequency electrical performance.

[0020] Optionally, the phased array antenna further includes an interconnect via structure, which includes: a first interconnect via electrically connecting the second circuit layer and the first circuit layer for transmitting radio frequency signals between the phased array chip and the antenna element; a second interconnect via electrically connecting the second circuit layer and the fourth circuit layer for transmitting control signals between the phased array chip and the digital control circuit; a third interconnect via electrically connecting the second circuit layer to the fifth circuit layer for realizing the common ground connection of the phased array antenna; a fourth interconnect via electrically connecting the second circuit layer and the fourth circuit layer for supplying power to the phased array chip; and a fifth interconnect via electrically connecting the second circuit layer to the fifth circuit layer for realizing parallel power supply.

[0021] Five types of functionally independent interconnect vias are used to handle the vertical interconnection functions of radio frequency signals, control signals, grounding, chip power supply, and multi-layer power supply parallel connection. This enables precise signal docking of each layer of circuits and avoids crosstalk problems caused by different types of signals sharing interconnection paths. At the same time, in conjunction with the layered circuit layout, all functions are vertically integrated within an integrated flexible multilayer board, eliminating the need for separate assembly and adapting to the high-precision processing requirements of the millimeter-wave band.

[0022] Thirdly, this application also provides an antenna module comprising the aforementioned phased array antenna. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1a This is an overall schematic diagram of an antenna element provided according to an embodiment of this application; Figure 1b This is a schematic diagram of one side surface of a substrate structure provided according to an embodiment of this application; Figure 1c This is a schematic diagram of the radiation characteristics of an antenna element according to an embodiment of this application; Figure 1d This is a schematic diagram of the radiation characteristics of an antenna element according to yet another embodiment of this application; Figure 2a This is a schematic diagram of the structure of a phased array antenna according to an embodiment of this application; Figure 2b This is a schematic diagram of the layout of a circuit layer according to an embodiment of this application; Figure 2cThis is a schematic diagram of the structure of a circuit layer according to yet another embodiment of this application; Figure 2d This is a schematic diagram of the interlayer circuitry according to one embodiment of this application. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages 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 embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0026] Unless otherwise specified, the experimental methods used in the following examples are conventional methods. Unless otherwise specified, the materials, reagents, methods, and instruments used are all conventional materials, reagents, methods, and instruments in the art, and can be obtained commercially by those skilled in the art.

[0027] It should be noted that, building upon the aforementioned background technologies, lightweight and foldable flexible phased array technology provides crucial support for expanding the application boundaries of phased arrays: scenarios such as spaceborne synthetic aperture radar (SAR) and direct-connect cellular satellite systems impose stringent constraints on the weight, storage volume, and cost of phased arrays, and flexible design can precisely meet these requirements. Simultaneously, in scenarios such as conformal installation on non-planar carriers and wearable devices, the fitability and flexibility of phased arrays have also become indispensable key performance indicators.

[0028] However, there is currently limited research on millimeter-wave flexible phased arrays, with the main technical challenges being: First, flexible dielectric substrates are generally too thin, making it difficult to meet the radiation profile requirements of millimeter-wave antenna elements. Traditional millimeter-wave patch antennas rely on a dielectric substrate of a certain thickness to achieve good radiation performance and bandwidth characteristics. However, flexible substrates are usually limited in thickness, and directly using conventional antenna designs will result in problems such as low radiation efficiency, narrow operating bandwidth, or resonant frequency shift. If additional reinforcement structures such as air layers or foam substrates are added, the flexibility and thinness of the antenna will be compromised, making it impossible to achieve integrated design with the back-end circuitry.

[0029] Secondly, the integrated design of multilayer flexible circuits is challenging, with a significant conflict between interlayer signal crosstalk and manufacturing precision. Phased arrays need to integrate multiple functions simultaneously, including antenna radiation, RF feeding, digital control, and power distribution. Traditional rigid boards can achieve signal isolation through multiple ground layers, but the precision of flexible board lamination and etching processes decreases significantly with the number of layers, making it difficult to lay out complete shielding ground layers and easily leading to severe interlayer signal crosstalk. If a multilayer separate assembly scheme is adopted, it will introduce assembly loss risks, and the alignment precision cannot meet the stringent requirements of the millimeter-wave band.

[0030] Third, the electrical and structural reliability of flexible substrates under bending and conformal conditions is insufficient. Curved bending will generate concentrated stress at the substrate, vias, and chip pads. Long-term repeated deformation can easily lead to failure problems such as pad cracking, pin desoldering, and interlayer peeling. At the same time, bending will cause ground plane deformation and impedance mismatch, further deteriorating signal isolation performance and radiation stability, which restricts the long-term use of flexible phased arrays in wearable, conformal installation and other scenarios.

[0031] Fourth, the power supply design is severely constrained by the number of flexible circuit board layers, making it difficult to balance power supply capacity and integration. Traditional phased arrays often employ parallel power supply schemes with independent full-surface power layers to ensure high current carrying capacity. However, this scheme requires a separate circuit layer, and the processing difficulty of multi-layer flexible circuit boards increases significantly with the number of layers. Too many layers not only increase manufacturing costs and reduce production yield but also increase the overall thickness of the substrate, weakening the bending performance and lightweight advantages of flexible phased arrays. If the power wiring space is reduced to control the number of layers, it will lead to insufficient power supply current capacity and excessive line voltage drop, failing to meet the stable power supply requirements of multi-channel phased array chips. At the same time, with limited inter-layer resources, power wiring and RF and control signal wiring encroach on each other's space, which can easily cause power supply noise crosstalk signal links and is not conducive to the compact arrangement of the array, further increasing the difficulty of integrated flexible phased arrays.

[0032] Based on this, to solve the above problems, this application provides an antenna element 100, applied to a phased array antenna, and the phased array antenna includes a substrate structure. For example... Figure 1a As shown, the antenna unit 100 includes a radiating patch structure 110, a groove structure disposed on the radiating patch structure, and a parasitic patch structure 130 disposed on one side of the radiating patch structure.

[0033] Among them, a phased array antenna can refer to an antenna array product composed of multiple antenna elements and phase control circuit devices, which can adjust the beam direction and shape through electronic control, thereby realizing signal transmission and reception and beam scanning in the millimeter wave band.

[0034] It should be noted that the phased array antenna includes a substrate structure, which can refer to a support carrier formed by stacking and bonding multiple layers of flexible dielectric materials, each of which can support the corresponding circuit structure or phased array radiation array.

[0035] For example, such as Figure 1b As shown, it is assumed that a radiating array structure is provided on a flexible dielectric substrate in the substrate structure, and the radiating array structure can be composed of multiple antenna elements 100.

[0036] Among them, the antenna unit can refer to the smallest radiating device that can complete the conversion between millimeter-wave electromagnetic waves and electrical signals, that is, the core functional unit that realizes electromagnetic energy conversion.

[0037] Specifically, the antenna unit may include a radiating patch structure 110, a groove structure disposed on the radiating patch structure, and a parasitic patch structure 130 disposed on the radiating patch structure.

[0038] Among them, the radiating patch structure 110 can refer to the radiating conductor of the antenna element, which can realize the mutual conversion of electrical energy and spatial electromagnetic waves.

[0039] For example, the radiating patch structure 110 may be a near-square metal copper foil patch formed on the surface of a flexible dielectric substrate in the substrate structure by an etching process.

[0040] The groove structure can refer to the hollow structure formed on the surface of the radiating patch by etching. It can control the resonance and polarization characteristics of the antenna by changing the current path on the patch surface.

[0041] Specifically, the groove structure can be set at the preset groove position of the radial patch structure.

[0042] The preset groove position can refer to a designated slotted area determined in advance by performance requirements, and the preset groove position is different for groove structures with different functions.

[0043] Specifically, the preset groove position may include a first groove position and a second groove position. Correspondingly, the groove structure includes a first groove structure 121 disposed at the first groove position and a second groove structure 123 disposed at the second groove position.

[0044] The first groove structure can refer to a slot structure that can realize the circular polarization radiation characteristics of the antenna element.

[0045] Specifically, the first groove structure 121 may include a first preset number of rectangular grooves, and the first preset number may be an even number. The rectangular grooves are symmetrically arranged with respect to the axis of the radial patch structure.

[0046] For example, please refer to Figure 1a In the figure, taking the first preset quantity of 2 as an example, the first rectangular slot 1211 and the second rectangular slot 1213 are symmetrically distributed along the two orthogonal central axes of the radial patch structure 110, and the whole is arranged in an orthogonal pattern.

[0047] It should be noted that the length and width of the rectangular slot are designed, for example, the length and width parameters can be 0.47mm×0.35mm, which can split the original single resonant mode on the patch surface into two sets of orthogonal radiation modes. The amplitudes of the two sets of modes are equal and the phase difference is 90°. The orthogonal electric field components rotate and superimpose in space over time to form circularly polarized radiation.

[0048] For example, please refer to Figure 1c , Figure 1c The diagram shows the linearly polarized radiation characteristics of the antenna element without the rectangular slot. However, after adding the rectangular slot, the radiation characteristics of the antenna element can be referenced. Figure 1d As shown in the figure, it is clear that after loading the rectangular slots, the antenna element exhibits circularly polarized radiation characteristics. Using an even number of rectangular slots symmetrically arranged along the axis ensures amplitude consistency between the two sets of orthogonal modes, improving the purity of circular polarization. Furthermore, the symmetrical structure prevents antenna pattern distortion, maintaining the symmetry of the radiation characteristics. The rectangular slot shape also facilitates precise control of the current path length, making it easier to match dual-resonant modes that meet the phase difference requirements.

[0049] Furthermore, the second groove structure can refer to a slot structure that can reduce the operating frequency of the antenna element.

[0050] Specifically, the second groove structure is a circular groove, and the position of the second groove is the geometric center of the radial patch structure.

[0051] For example, please refer to Figure 1a A single second groove structure 123 (circular groove) is formed at the geometric center of the radiating patch structure 110, with the center of the groove coinciding with the geometric center of the radiating patch. The circular groove at the center forces the induced current on the patch surface to travel around the edge of the groove, effectively lengthening the current flow path. The longer current path corresponds to an increase in the equivalent resonant wavelength, which can reduce the resonant frequency of the antenna without increasing the patch size or the dielectric thickness.

[0052] Placing the circular slot at the geometric center of the radiating patch serves two purposes: firstly, the centrally symmetrical shape does not disrupt the orthogonal mode symmetry formed by the first groove structure, ensuring that the circular polarization performance is unaffected; secondly, a single central slot can achieve full-domain current path elongation, resulting in high frequency reduction efficiency, and the circular slot provides uniform stress distribution, making it less prone to structural cracking under bending conditions.

[0053] This method, which involves arranging two types of groove structures with different functions at preset positions, can simultaneously achieve polarization and frequency control on the same radiating patch without adding additional structural layers, thus meeting the design requirements of circular polarization and low profile on a thin substrate.

[0054] Furthermore, a parasitic patch structure 130 is also provided on one side of the radiating patch structure 110, and the parasitic patch structure and the groove structure are coplanarly disposed on the same side surface of the substrate structure to form a single-layer radiating structure.

[0055] The parasitic patch structure 130 can refer to an additional radiating conductor that operates by near-field electromagnetic coupling, which is not directly fed through wires and can extend the operating bandwidth of the antenna element.

[0056] Specifically, the parasitic patch structure may include a second preset number of parasitic branches, the second preset number being an even number, and the parasitic branches are arranged symmetrically around the geometric center of the radiating patch structure.

[0057] For example, please continue to refer to Figure 1a In the figure, taking the second preset quantity of 4 as an example, the first parasitic branch 131, the second parasitic branch 133, the third parasitic branch 135 and the fourth parasitic branch 137 are respectively arranged on the outer side of the four sides of the radiating patch, and are centrally symmetrically distributed with the geometric center of the radiating patch as the reference.

[0058] Specifically, without parasitic patches, the 90° phase difference of the radiating patch dual-resonant modes is only satisfied at a very narrow frequency range. Off-center, the phase difference rapidly deviates from 90°, the axial ratio deteriorates, and thus the circular polarization bandwidth is very narrow. The role of parasitic patches is to alter the phase frequency response of the two sets of orthogonal modes through parasitic coupling, maintaining the phase difference between them around ±90° over a wider frequency band, while simultaneously optimizing the amplitude balance of the orthogonal components, ultimately expanding the circular polarization axial ratio bandwidth.

[0059] The shorter the length of the parasitic patch, the less significant the effect of parasitic coupling in the operating frequency band. As the length of the parasitic patch increases, the axial ratio bandwidth of the circular polarization gradually widens. However, when the length exceeds 1.32 mm, the resonant frequencies of the two resonant modes become excessively close, and the axial ratio bandwidth begins to narrow.

[0060] By employing an even number of parasitic stubs symmetrically arranged around the perimeter, consistent coupling strength in all directions can be ensured, preventing tilting and distortion of the radiation pattern. Furthermore, parasitic coupling can further widen the bandwidth coverage and improve frequency offset tolerance under bending conditions.

[0061] Furthermore, the parasitic patch structure 130 and the radiating patch structure 110 are arranged at intervals, that is, there are gaps between the parasitic patch structure 130 and the radiating patch structure 110, so that the parasitic patch structure can be used to extend the operating bandwidth of the antenna element.

[0062] It should be noted that the gap refers to the transverse insulating gap between the parasitic patch structure 130 and the radiating patch structure 110 in the same plane, and there is no direct metal contact between the two.

[0063] Furthermore, experiments revealed that when no gap exists, the antenna's relative bandwidth is only about 0.6%. However, when a gap is added to form a gap coupling structure, the antenna's relative bandwidth is expanded. It should be noted that the gap primarily modulates the mode-pulling effect of the two sets of orthogonal composite modes by changing the gap coupling strength. When the gap is 0.1 mm, the coupling strength is too high, excessively widening the resonant frequencies of the two sets of orthogonal composite modes, making it difficult to simultaneously satisfy the amplitude and phase conditions required for circular polarization over a wide frequency range, resulting in a narrow axial ratio bandwidth. When the gap is between 0.2 mm and 0.3 mm, the coupling strength is moderate, and the phase frequency response of the orthogonal modes is effectively modulated, achieving the optimal circular polarization axial ratio bandwidth. When the gap further increases to 0.4 mm or more, the main parasitic coupling effect is weakened, the parasitic patch's ability to disturb the orthogonal mode field decreases, and the circular polarization axial ratio bandwidth gradually degrades.

[0064] For example, the size of the gap can preferably be 0.2 mm. Experiments have shown that after setting a 0.2 mm gap to form a gap coupling structure, the relative bandwidth of the antenna can reach 11.9%.

[0065] In addition, the radiating patch structure 110, the groove structure and the parasitic patch structure 130 are coplanarly disposed on the same side surface of the substrate structure to form a single-layer radiating structure for receiving and transmitting millimeter waves.

[0066] It should be noted that coplanar setup means that all radiation-related metal structures are fabricated in the same metal layer on the same side of the substrate structure, without the need for stacking multiple radiation patches across layers or additional three-dimensional structures.

[0067] The entire antenna unit can radiate and receive millimeter-wave signals using only a single-layer metal pattern. Specifically, after the radio frequency signal is fed into the radiating patch structure, a high-frequency induced current is excited on the patch surface. This current is modulated through a groove structure to form a biorthogonal mode that meets the circular polarization requirements. Simultaneously, it excites surrounding parasitic patch structures through gap coupling to radiate together. Ultimately, a millimeter-wave circularly polarized electromagnetic wave is synthesized in space, and the receiving process is the reverse of the radiation process. This single-layer coplanar architecture requires fewer processing steps, is compatible with the integrated processing technology of flexible substrates, and exhibits uniform structural stress during bending, resulting in stronger performance stability.

[0068] It should be noted that after forming the groove structure on the radiating patch structure, the biorthogonal radiation modes can be separated by changing the current path, thus satisfying the basic requirements of circular polarization. The specific shape and depth of the groove can be flexibly adjusted according to actual experimental needs to optimize performance.

[0069] In the above embodiments, a radiating patch structure is used to provide basic millimeter-wave radiation capability, a groove structure is used to simultaneously achieve polarization control and resonant frequency control, and a parasitic patch structure with gaps is used to expand the working bandwidth. All three are coplanarly integrated in a single-layer metal structure, which can simultaneously meet the performance requirements of circular polarization, low profile and wide bandwidth on a thin flexible dielectric substrate. Excellent radiation characteristics can be achieved without a multi-layer stacked architecture, which is suitable for the integrated requirements of flexible phased arrays.

[0070] This application embodiment also provides a phased array antenna 200, which includes a substrate structure 210 and a circuit structure 220.

[0071] The substrate structure 210 can refer to a support carrier formed by stacking and bonding multiple layers of flexible dielectric materials, each of which can support the corresponding circuit structure or phased array antenna array.

[0072] Specifically, the substrate structure 210 includes multiple layers of flexible dielectric substrates stacked sequentially, and adjacent flexible dielectric substrates are bonded together by a flexible adhesive layer.

[0073] Among them, the flexible adhesive layer can refer to the adhesive functional layer used to bond adjacent flexible dielectric substrates. It can integrate multiple independent flexible dielectric substrates into an integrated flexible stacked structure through interlayer adhesion.

[0074] Specifically, the flexible adhesive layer can be prepared using a semi-cured adhesive material, which is melted and cross-linked after being treated with high temperature and high pressure in the multilayer flexible board pressing process, so that the upper and lower flexible media substrates are tightly bonded into a whole, and the overall bendability of the substrate can still be maintained after the bonding is completed.

[0075] Flexible dielectric substrates can refer to the basic dielectric substrates that support circuit structures and radiating devices, providing physical support for each layer of metal circuits.

[0076] Specifically, the flexible dielectric substrate can be made of a flexible insulating dielectric material that has good mechanical flexibility and high-frequency dielectric properties.

[0077] Preferably, the material used to prepare the flexible dielectric substrate can be polyimide or liquid crystal polymer.

[0078] Polyimide possesses excellent mechanical flexibility and high-temperature resistance, making it suitable for multilayer lamination processes and long-term bending conditions. Liquid crystal polymers, on the other hand, exhibit lower dielectric loss, resulting in less signal transmission loss in the millimeter-wave high-frequency band.

[0079] Using the two materials mentioned above to prepare flexible dielectric substrates can ensure the flexibility and bendability of the substrate while also taking into account the high-frequency transmission performance in the millimeter-wave band.

[0080] It should be noted that the materials used to prepare flexible dielectric substrates are not limited to the two mentioned above. As long as they can meet the requirements for flexible bending and the electrical performance requirements of the millimeter-wave band, they can be adapted and selected according to the actual working conditions.

[0081] Specifically, the substrate structure 210 includes, from bottom to top, a first flexible dielectric substrate 211, a first flexible adhesive layer 212, a second flexible dielectric substrate 213, a second flexible adhesive layer 214, a third flexible dielectric substrate 215, a third flexible adhesive layer 216, and a fourth flexible dielectric substrate 217 stacked sequentially.

[0082] Furthermore, a circuit structure 220 is also provided on the surface of the flexible dielectric substrate.

[0083] The circuit structure 220 can refer to a collection of metal functional circuits formed on the surface of various flexible dielectric substrates through etching processes, which can realize functions such as signal transmission, power distribution, control and regulation, and electromagnetic radiation.

[0084] Specifically, the circuit structure 220 includes a first circuit layer 221, a second circuit layer 222, a third circuit layer 223, a fourth circuit layer 224, and a fifth circuit layer 225.

[0085] The first circuit layer 221 can refer to the circuit structure layer located at the top of the substrate structure, which carries the phased array radiation elements.

[0086] For example, in such Figure 2a In the phased array antenna shown, the first circuit layer 221 can be located on the upper surface of the fourth flexible dielectric substrate 217. The first circuit layer includes at least one of the aforementioned antenna elements 100 for radiating and receiving millimeter-wave signals, thus forming a phased array radiation array.

[0087] Understandably, please continue to refer to Figure 1b Multiple antenna elements are evenly arranged in a preset row and column pattern to form an array, and each antenna element can independently transmit and receive millimeter-wave signals. With the phased array chip in the phased array antenna controlling the phase of each element, the electronically controlled scanning of the overall beam pointing of the array can be achieved, completing the core beam scanning function of the phased array.

[0088] The second circuit layer 222 can refer to a circuit structure layer that carries the core device and the external interface. This second circuit layer 222 is located on the lower surface of the first flexible dielectric substrate 211, and the second circuit layer is provided with a phased array chip and an external connector. The external connector can be used to realize the interaction with external signals.

[0089] Specifically, such as Figure 2a As shown, the phased array chip 310 and external connector are soldered onto the surface of the second circuit layer 222.

[0090] Among them, the phased array chip can refer to a phased array transceiver chip with multi-channel amplitude and phase modulation capability, which can independently control the amplitude and phase of each radio frequency signal, and work with the array unit to realize the electronically controlled scanning of beam pointing.

[0091] Specifically, phased array chips can be fixed to the surface of the circuit layer using a surface mount soldering process. For example, Figure 2a The phased array chip 310 shown in the image can be packaged in a ball grid array, with a matrix of solder ball contacts 311 arranged on its bottom surface, which can support a large number of interfaces for multi-channel chips.

[0092] In addition, phased array chips can also be packaged in a quad flat no-lead (QFN) package. This method results in a compact package size and reduces stress concentration during bending.

[0093] It should be noted that a single phased array chip can integrate multiple channels and simultaneously control the amplitude and phase of multiple antenna elements.

[0094] For example, the phased array chip in this embodiment can adopt an 8-channel design, with a total of 16 chips, which drive 128 antenna elements to form an array.

[0095] External connectors refer to the connection interface devices between phased array arrays and external devices, enabling the external input and output of radio frequency signals, control commands, and power supplies.

[0096] Specifically, the external connectors may include an RF signal connector 321, a control signal connector 323, and a power signal connector 325.

[0097] Understandably, the RF signal connector, control signal connector, and power signal connector correspond to the external access of RF signals, control signals, and power supply, respectively. All external signals are accessed into the array through this layer, and the control outputs of all chips are also distributed through this layer, thus enabling complete external signal interaction functionality.

[0098] Furthermore, an RF power supply circuit is also printed on the second circuit layer 222.

[0099] For example, please refer to Figure 2bThe radio frequency (RF) power supply circuit includes an RF matching circuit 331, a power distribution / combining circuit 333, a first numerical control circuit 410, and a first power supply circuit 510.

[0100] The power distribution / combining circuit 333 can be implemented using a Wilkinson line structure for radio frequency transmission, connecting the radio frequency connectors to each phased array chip, and evenly distributing the externally input radio frequency signal to multiple chips. The radio frequency matching circuit 331 can be used to achieve impedance matching between the chips and the antenna elements, reducing signal reflection loss.

[0101] The first CNC circuit 410 can serve as a cross-layer bypass branch of the digital control circuit, working in conjunction with the main control circuit of the fourth circuit layer to complete the wiring, avoiding cross-over conflicts in single-layer wiring, and finally connecting to the control signal connector.

[0102] The first power supply circuit 510 can provide a power supply circuit for the phased array chip of this layer directly on the one hand, and vertically interconnect with the power supply circuits of other circuit layers through interconnecting vias to form a parallel power supply network.

[0103] The third circuit layer 223 can refer to a circuit structure layer that undertakes the function of shielding the underlying signal. It is located on the upper surface of the first flexible dielectric substrate 211, and the third circuit layer is provided with a first metal ground structure, which can be used to achieve interlayer shielding and isolation.

[0104] The first metal ground structure can refer to a continuous metal ground plane laid above the bottom layer circuit, which is a complete ground structure that provides a unified return reference for the bottom layer radio frequency and digital signals and undertakes the function of interlayer shielding. Specifically, the main area of ​​the third circuit layer is a continuous copper foil, which constitutes the complete first metal ground structure.

[0105] It should be noted that the third circuit layer 223 only has a small area of ​​second power supply circuit 520 arranged in the edge area. The complete metal ground plane (i.e. the first metal ground structure) can provide a low impedance return path for the radio frequency signals and digital signals of the bottom layer, and at the same time block the electromagnetic radiation of the bottom circuit to the upper layer of the substrate through the metal shielding effect, so as to avoid the bottom signal crosstalk to the middle layer and the top layer radiation circuit, and achieve signal isolation between layers.

[0106] The fourth circuit layer 224 can refer to a circuit structure layer that undertakes the functions of control signal distribution and power distribution. It is located on the upper surface of the second flexible dielectric substrate 213, and the fourth circuit layer is provided with a numerical control circuit, which can be used to realize the distribution of control signals.

[0107] Specifically, such as Figure 2cAs shown, the fourth circuit layer 224 is equipped with a second numerical control circuit 420, a third power supply circuit 530, and a fourth power supply circuit 540.

[0108] Among them, the second numerical control circuit 420 can refer to the backbone wiring network of digital control signals, that is, the core circuit set that undertakes the collection and distribution of all phased array chip control signals.

[0109] The third power supply circuit 530 can refer to the main power supply bus structure of the phased array chip, that is, it serves as the main power supply node to receive DC power input and distribute power supply current to each phased array chip.

[0110] The fourth power supply circuit 540 can refer to a large area of ​​power copper foil laid on this layer, that is, it is connected in parallel with the power supply circuits of other layers through vertical interconnecting vias to jointly improve the overall power supply current carrying capacity.

[0111] Specifically, the digital control lines of the 16 phased array chips are converged to this layer for unified wiring. All control lines eventually converge and are connected to the control signal connector to realize the synchronous control of multiple chips by external control signals.

[0112] It should be noted that due to the large number of chips and control lines, the space for single-layer wiring is limited, and line crossings are prone to occur when multiple traces are arranged. Therefore, at the line crossing points, interconnect vias can be used to bypass the crossings and extend to the second circuit layer to avoid crossover conflicts in single-layer wiring. At the same time, this layer also has a continuous power copper foil busbar as a main power supply structure, which can branch out into multiple lines to connect to the power supply pads of each phased array chip.

[0113] The fifth circuit layer 225 can refer to the circuit structure layer that undertakes the radiation shielding function of the top layer. It is located on the lower surface of the third flexible dielectric substrate 215, and the fifth circuit layer is provided with a second metal ground structure, which can be used to suppress interlayer signal crosstalk.

[0114] The second metal ground structure can refer to a continuous metal ground plane laid below the top antenna, which is a ground structure that serves as both an antenna reflector and an interlayer signal shield.

[0115] Specifically, the fifth circuit layer 225 has a similar layout to the third circuit layer 223, and its main area is also a continuous whole surface of metal copper foil, forming a complete second metal ground structure.

[0116] Furthermore, the fifth circuit layer 225 only has a small area of ​​fifth power supply circuit 550 arranged in the edge region. This metal ground plane serves as a reflective ground plane for the top antenna unit, ensuring the directional radiation characteristics of the antenna. On the other hand, it can isolate the digital control circuit and power supply circuit of the intermediate layer, prevent signal noise from the intermediate layer from coupling to the top antenna unit, suppress inter-layer signal crosstalk, and ensure the purity of the radiation performance of the top layer.

[0117] It should be noted that no additional functional circuits are installed on the upper surface of the third flexible dielectric substrate and the lower surface of the fourth flexible dielectric substrate. This avoids interference from other lines with the radiation characteristics of the top antenna element and ensures the stability of the antenna radiation performance.

[0118] By centralizing the core functional circuits on the second, fourth, and first circuit layers, and setting the third and fifth circuit layers as complete metal ground layers, all functions of radiation, power supply, control, power supply, and shielding isolation can be achieved simultaneously within a five-layer circuit architecture. This simplifies the total number of substrate layers, reduces the processing difficulty and bending / delamination risk of multilayer flexible boards, and effectively suppresses interlayer signal crosstalk through the double-layer metal ground structure, thus balancing flexible process adaptability and high-frequency electrical performance.

[0119] Further, please continue to refer to Figure 2a The phased array antenna 200 also includes an interconnect via structure 230. The interconnect via structure 230 can refer to a metallized vertical conductive path that penetrates the flexible dielectric substrate and the flexible adhesive layer, and is used to realize vertical electrical connection between different layers of circuit structure.

[0120] Specifically, the interconnect via structure 230 may include: a first interconnect via 231, a second interconnect via 232, a third interconnect via 233, a fourth interconnect via 234, and a fifth interconnect via 235.

[0121] The first interconnect via 231 can refer to a vertical interconnect path used for transmitting radio frequency signals. It electrically connects the second circuit layer and the first circuit layer and can be used to transmit radio frequency signals between the phased array chip and the antenna unit.

[0122] Specifically, the first interconnect via 231 vertically penetrates through each intermediate dielectric and adhesive layer, with one end connected to the output of the RF matching circuit 331 of the second circuit layer and the other end connected to the feed point of the corresponding antenna element in the first circuit layer 221. The amplitude-modulated and phase-modulated RF signal output by the phased array chip is transmitted vertically to the top antenna element through the RF matching circuit of the second circuit layer and then through the first interconnect via, and is finally radiated into space by the antenna element. The receiving process is the reverse transmission, thereby realizing the cross-layer vertical transmission of RF signals.

[0123] The second interconnect via 232 can refer to a vertical interconnect path used for transmitting digital control signals. It electrically connects the second circuit layer and the fourth circuit layer and can be used to transmit control signals between the phased array chip and the digital control circuit.

[0124] Specifically, the second interconnecting via vertically penetrates the first flexible dielectric substrate and the first flexible adhesive layer, with one end connected to the control pin of the phased array chip in the second circuit layer and the other end connected to the second numerical control circuit in the fourth circuit layer. Externally input control signals enter the second circuit layer via the control connector and can then be transmitted through the second interconnecting via to the control bus in the second numerical control circuit of the fourth circuit layer, and subsequently distributed to each phased array chip, enabling remote control of the chip's phase and amplitude parameters.

[0125] The third interconnect via 233 can refer to a vertical interconnect path used to realize ground connection of the strata. It is electrically connected to the second to fifth circuit layers and can be used to realize the ground connection of phased array antennas.

[0126] It should be noted that, except for the first circuit layer (i.e., the circuit layer containing the antenna elements), all other circuit layers have ground structures. Therefore, the third interconnect via can be used to vertically penetrate the dielectric and adhesive layers of the corresponding layers, directly connecting the chip ground pin of the second circuit layer, the first metal ground structure of the third circuit layer, the ground path of the fourth circuit layer, and the second metal ground structure of the fifth circuit layer. This ensures that the two metal ground layers and the chip ground are at the same potential, forming a unified ground reference plane. This not only ensures the integrity of the signal return path but also enhances the shielding and isolation effect of the double ground layer, further reducing interlayer crosstalk.

[0127] The fourth interconnect via 234 can refer to a vertical interconnect path used for the main power supply transmission of the chip. It electrically connects the second circuit layer and the fourth circuit layer and can be used to supply power to the phased array chip.

[0128] Specifically, the fourth interconnecting via vertically penetrates the first flexible dielectric substrate and the first flexible adhesive layer, with one end connected to the power supply pad of the phased array chip in the second circuit layer and the other end connected to the third power supply circuit of the fourth circuit layer. After the external DC power supply is connected, the main current is first transmitted to the third power supply circuit (main power supply bus) of the fourth circuit layer, and then vertically transmitted through the fourth interconnecting via to the power supply pin of each phased array chip, providing the chip with operating power.

[0129] The fifth interconnect via 235 can refer to a vertical interconnect path used to realize the parallel connection of multiple power supplies. It electrically connects the second circuit layer to the fifth circuit layer and can be used to realize the parallel power supply.

[0130] Specifically, such as Figure 2dAs shown, the fifth interconnecting via vertically penetrates the dielectric and adhesive layers corresponding to the second to fifth circuit layers, conducting all the power copper foil areas along the edges of each layer. The first power circuit of the second circuit layer, the second power circuit of the third circuit layer, the third and fourth power circuits of the fourth circuit layer, and the fifth power circuit of the fifth circuit layer are connected in parallel through the fifth interconnecting via to form a whole, jointly constituting the power supply network. This method of multi-layer partitioning and vertically parallelizing power copper foil eliminates the need for a separate full-surface power layer. It can increase the total current carrying capacity through the stacking of multiple copper foil layers, meeting the high current power supply requirements of multiple chips within a limited number of layers, and overcoming the processing constraints of the limited number of layers in flexible boards.

[0131] It should be noted that the placement of the interconnect vias shown in the figure is only an exemplary arrangement. In actual applications, adjustments can be made according to the interface layout of each circuit layer. The diameter of the interconnect vias can be designed based on the impedance matching requirements of the transmitted signals, as long as stable transmission of the corresponding signals can be ensured.

[0132] Five types of functionally independent interconnect vias are used to handle the vertical interconnection functions of radio frequency signals, control signals, grounding, chip power supply, and multi-layer power supply parallel connection. This enables precise signal docking of each layer of circuits and avoids crosstalk problems caused by different types of signals sharing interconnection paths. At the same time, in conjunction with the layered circuit layout, all functions are vertically integrated within an integrated flexible multilayer board, eliminating the need for separate assembly and adapting to the high-precision processing requirements of the millimeter-wave band.

[0133] In the above embodiments, an integrated architecture of stacked and bonded multilayer flexible dielectric substrates is adopted to integrate the antenna radiating unit, RF feed, digital control and parallel power supply circuits into the same flexible substrate. With the shielding design of double-layer metal ground, the insufficient radiation performance and interlayer crosstalk of thin flexible substrates are effectively overcome while ensuring the flexible, bendable and conformal characteristics, so as to realize the high integration and high performance integrated design of millimeter wave phased array.

[0134] This application also provides an antenna module comprising the phased array antenna described above.

[0135] For specific limitations on an antenna module, please refer to the limitations on a phased array antenna mentioned above, which will not be repeated here.

[0136] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0137] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0138] It should also be noted that 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.

[0139] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. Since they are fundamentally similar to the method embodiments, the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0140] The above description is merely an embodiment of this application and is not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

[0141] Although embodiments of this application have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of this application, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. An antenna element, characterized in that, Applied to a phased array antenna, the phased array antenna includes a substrate structure; the antenna element includes: Radiation patch structure; A groove structure provided on the radial patch structure; A parasitic patch structure is disposed on one side of the radiating patch structure; the parasitic patch structure is arranged at intervals with the radiating patch structure, and the parasitic patch structure is used to extend the operating bandwidth of the antenna element; The radiating patch structure, the groove structure, and the parasitic patch structure are coplanarly disposed on the same side surface of the substrate structure to form a single-layer radiating structure, which is used to receive and transmit millimeter waves.

2. The antenna element according to claim 1, characterized in that, The groove structure is disposed at a preset groove position of the radial patch structure; the preset groove position includes a first groove position and a second groove position; the groove structure includes: A first groove structure is disposed at the position of the first groove; wherein, the first groove structure is used to realize the circular polarization radiation characteristics of the antenna element; A second groove structure is provided at the location of the second groove; wherein, the second groove structure is used to reduce the operating frequency of the antenna element.

3. The antenna element according to claim 2, characterized in that, The first groove structure includes a first preset number of rectangular grooves, the first preset number being an even number, and the rectangular grooves are symmetrically arranged with respect to the axis of the radiating patch structure.

4. The antenna element according to claim 2, characterized in that, The second groove structure is a circular groove; the position of the second groove is the geometric center of the radial patch structure.

5. The antenna element according to claim 1, characterized in that, The parasitic patch structure includes a second preset number of parasitic branches, the second preset number being an even number, and the parasitic branches are symmetrically arranged around the radial patch structure with respect to the geometric center of the radial patch structure.

6. A phased array antenna, characterized in that, include: A substrate structure; wherein the substrate structure comprises multiple layers of flexible dielectric substrates stacked sequentially; and adjacent flexible dielectric substrates are bonded together by a flexible adhesive layer; A circuit structure located on the surface of the flexible dielectric substrate; wherein the circuit structure includes a first circuit layer located on the top layer of the substrate structure; the first circuit layer includes at least one antenna element as described in any one of claims 1 to 5, for radiating and receiving millimeter-wave signals, forming a phased array radiation array.

7. The phased array antenna according to claim 6, characterized in that, The flexible dielectric substrate is prepared from polyimide or liquid crystal polymer.

8. The phased array antenna according to claim 6, characterized in that, The substrate structure comprises, from bottom to top, a first flexible dielectric substrate, a first flexible adhesive layer, a second flexible dielectric substrate, a second flexible adhesive layer, a third flexible dielectric substrate, a third flexible adhesive layer, and a fourth flexible dielectric substrate, stacked sequentially. The first circuit layer is located on the upper surface of the fourth flexible dielectric substrate; The circuit structure also includes: A second circuit layer is located on the lower surface of the first flexible dielectric substrate, and the second circuit layer is provided with a phased array chip and an external connector; the external connector is used to realize interaction with external signals; A third circuit layer is located on the upper surface of the first flexible dielectric substrate, and the third circuit layer is provided with a first metal ground structure; the first metal ground structure is used to achieve interlayer shielding and isolation. A fourth circuit layer is located on the upper surface of the second flexible dielectric substrate, and the fourth circuit layer is provided with a numerical control circuit; the numerical control circuit is used to realize the distribution of control signals; The fifth circuit layer is located on the lower surface of the third flexible dielectric substrate, and the fifth circuit layer is provided with a second metal ground structure; the second metal ground structure is used to suppress interlayer signal crosstalk.

9. The phased array antenna according to claim 8, characterized in that, The phased array antenna further includes an interconnecting via structure, the interconnecting via structure comprising: A first interconnecting via electrically connects the second circuit layer and the first circuit layer, and is used to transmit radio frequency signals between the phased array chip and the antenna unit; A second interconnecting via electrically connects the second circuit layer and the fourth circuit layer, and is used to transmit control signals between the phased array chip and the numerical control circuit; A third interconnecting via electrically connects the second circuit layer to the fifth circuit layer, used to realize the common ground connection of the phased array antenna; A fourth interconnecting via electrically connects the second circuit layer and the fourth circuit layer, and is used to supply power to the phased array chip; A fifth interconnecting via electrically connects the second circuit layer to the fifth circuit layer, enabling parallel power supply.

10. An antenna module, characterized in that, Includes the phased array antenna as described in any one of claims 6 to 9.

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