Conformal phased array antenna based on flexible liquid crystal substrate and preparation method

Abstract

The application discloses a kind of conformal phased array antenna based on flexible liquid crystal substrate and preparation method, belong to antenna technical field.The antenna includes multilayer flexible liquid crystal polymer substrate and integrated on it antenna radiation unit, feed network, liquid crystal phase shift structure and embedded radio frequency chip, liquid crystal phase shift structure is integrally formed with substrate, vertical interconnection structure inside substrate is used to realize radio frequency connection between each component, and the whole is integrally formed by multilayer compression process;When preparing, conductive pattern and liquid crystal phase shift structure are prepared on substrate in sequence, laminated integrally after embedding radio frequency chip, and then vertical interconnection structure is prepared to complete interconnection;The application uses vertical interconnection structure to replace gold wire bonding, integrates liquid crystal phase shift structure in substrate, eliminates exposed bonding interface, and improves mechanical reliability and high-frequency transmission performance under curved surface conformal scenario.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, specifically to a conformal phased array antenna based on a flexible liquid crystal substrate and its fabrication method. Background Technology

[0002] Phased array antennas, with their rapid beam scanning and flexible pointing control capabilities, have become core equipment for satellite communications, radar detection, and next-generation mobile communications. As applications extend to airborne skins, wearable devices, and curved conformal platforms, antennas are shifting from traditional rigid flat panel forms to flexible substrate structures, represented by liquid crystal polymers (LCPs), to meet the demands of bending, bonding, and thinning. LCP substrates possess excellent dielectric properties across the microwave to millimeter-wave (up to 110 GHz) frequency bands and can be fabricated into complex multilayer structures using low-cost PCB processes, thus attracting continuous attention in the field of flexible phased array antennas.

[0003] Currently, mainstream flexible phased array antenna solutions generally adopt a "split-type" structure. As disclosed in Chinese patent CN115483536B (Flexible Phased Array Antenna and Fabrication Method), this solution fabricates the feed port module, power divider module, and phased array antenna elements on the same LCP substrate. The phase shifter module is then bonded to the substrate using a micro-assembly process. The phase shifter module, power divider module, and phased array antenna elements are connected via gold wire bonding for radio frequency (RF) communication. In this solution, the micro-coaxial feed port module and power divider module fabricated on the LCP substrate can achieve feed and power division functions up to 110 GHz.

[0004] However, this "split" solution artificially divides a complete RF link into two parts: a "substrate" and an "external module," which are connected by exposed gold wire bonding structures. This structure has the following problems: Gold wire bonding structures face serious mechanical reliability issues in curved conformal scenarios: when the bending angle of the LCP substrate is greater than 10°, the bending stress increases rapidly with the increase of the bending angle. The integrated assembly technology of curved conformal antennas also points out that large curvature curved conformal antennas face problems such as "large substrate stress and difficult molding". When flexible phased array antennas are attached to conformal platforms such as curved skin of aircraft, the vibration and repeated deformation during flight will continuously pull on the exposed gold wire bonding points, causing the bonding points to crack or even fall off, which directly affects the long-term service reliability of the antenna.

[0005] The high-frequency signal loss caused by gold wire bonding is a prominent problem: the signal needs to go through multiple transitions from the chip pad to the substrate trace and then to the radiating unit, which lengthens the signal transmission path and increases parasitic capacitance and inductance. When the radio frequency signal is transmitted in the high-frequency band, there will be obvious loss and phase deviation, resulting in a decrease in beam pointing accuracy.

[0006] The manufacturing process is complex and yield control is difficult: Since the phase shifter module is mounted after the fact, its processing technology is independent of the lamination process of the LCP substrate and it is difficult to complete in the same production process. There are many assembly steps, and even a small change in the gold wire bonding process parameters may cause a significant disturbance to the transmission performance. Summary of the Invention

[0007] The purpose of this invention is to provide a conformal phased array antenna based on a flexible liquid crystal substrate and its fabrication method. The antenna uses a vertical interconnect structure to replace gold wire bonding and integrates the liquid crystal phase-shifting structure inside the substrate, eliminating exposed bonding interfaces and improving mechanical reliability and high-frequency transmission performance in curved conformal scenarios.

[0008] The objective of this invention can be achieved through the following technical solutions: This application provides a conformal phased array antenna based on a flexible liquid crystal substrate, comprising: A multilayer flexible liquid crystal polymer substrate, comprising at least two laminated liquid crystal polymer dielectric layers; An antenna radiating element is disposed on the outermost surface of the multilayer flexible liquid crystal polymer substrate; A power supply network is disposed between the internal layers of the multilayer flexible liquid crystal polymer substrate; The liquid crystal phase-shifting structure is an integral structure with the multilayer flexible liquid crystal polymer substrate. The liquid crystal phase-shifting structure includes a liquid crystal material receiving cavity located inside the multilayer flexible liquid crystal polymer substrate, a pair of phase-shifting electrodes disposed on the inner wall of the liquid crystal material receiving cavity, and liquid crystal material filling the liquid crystal material receiving cavity. The liquid crystal phase-shifting structure changes the effective dielectric constant of the liquid crystal material by applying a bias voltage to the pair of phase-shifting electrodes, thereby realizing continuous modulation of the phase of the radio frequency signal. An embedded radio frequency chip is embedded in a chip embedding cavity inside the multilayer flexible liquid crystal polymer substrate. The embedded radio frequency chip integrates at least radio frequency signal amplification function, and also integrates control function for applying the bias voltage to the liquid crystal phase shifting structure. A vertical interconnect structure is disposed inside the multilayer flexible liquid crystal polymer substrate, wherein the vertical interconnect structure is a metallized blind via, a buried via, or a copper paste interconnect structure. The antenna radiating element, the feeding network, the liquid crystal phase-shifting structure, and the multilayer flexible liquid crystal polymer substrate are integrally formed by a multilayer lamination process. The embedded radio frequency chip is connected to the feed network via the vertical interconnect structure, and the feed network is connected to the antenna radiating unit via the liquid crystal phase shift structure. The embedded radio frequency chip is also electrically connected to the phase-shifting electrode through the vertical interconnect structure to apply the bias voltage to the liquid crystal phase-shifting structure.

[0009] A method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate, comprising the following steps: S1. A multilayer flexible liquid crystal polymer substrate is provided, wherein the multilayer flexible liquid crystal polymer substrate includes at least two liquid crystal polymer dielectric layers; S2. Conductive patterns of antenna radiating elements and feed networks are prepared on at least one layer of the liquid crystal polymer dielectric layer; S3. A liquid crystal phase-shifting structure is prepared inside the multilayer flexible liquid crystal polymer substrate, specifically including: forming a liquid crystal material receiving cavity in the liquid crystal polymer dielectric layer, preparing a phase-shifting electrode pair on the inner wall of the liquid crystal material receiving cavity, filling the liquid crystal material receiving cavity with liquid crystal material, and sealing the liquid crystal material receiving cavity around its perimeter. S4. A chip embedding cavity is prepared inside the multilayer flexible liquid crystal polymer substrate; S5. Embed the radio frequency chip in the chip embedding cavity. The radio frequency chip integrates at least radio frequency signal amplification function and control function for applying bias voltage to the liquid crystal phase shifting structure. S6. The liquid crystal polymer dielectric layers are laminated and pressed together by a lamination process, so that the antenna radiating unit, the feed network, the liquid crystal phase shifting structure and the multilayer flexible liquid crystal polymer substrate are integrally formed. S7. A vertical interconnect structure is prepared inside the multilayer flexible liquid crystal polymer substrate, wherein the vertical interconnect structure is a metallized blind via, a buried via, or a copper paste interconnect structure. S8. The RF chip is connected to the feed network via the vertical interconnect structure, the feed network is connected to the antenna radiating unit via the liquid crystal phase-shifting structure, and the RF chip is electrically connected to the phase-shifting electrode via the vertical interconnect structure to apply the bias voltage to the liquid crystal phase-shifting structure.

[0010] The beneficial effects of this invention are as follows: This invention integrates a liquid crystal phase-shifting structure into a multilayer flexible liquid crystal polymer substrate and integrally forms it with the substrate. Simultaneously, a radio frequency (RF) chip is embedded in a chip embedding cavity within the substrate. A vertical interconnect structure located within the substrate replaces the traditional exposed gold wire bonding, enabling RF connectivity between functional modules. This effectively solves the technical problem in existing "split-type" solutions where the gold wire bonding structure experiences a sharp increase in stress when the bending angle exceeds 10° in curved conformal scenarios, leading to bonding point cracks or even detachment due to flight vibration and repeated deformation. The invention achieves the technical effect of having the bending stress borne by the entire substrate rather than concentrated at the bonding points, significantly improving the mechanical reliability and service life of the antenna in curved conformal scenarios. This invention utilizes a vertical interconnect structure within the substrate to connect the embedded RF chip, feed network, liquid crystal phase-shifting structure, and antenna radiating element, transforming the signal transmission path from multiple transitions to a single continuous path. Simultaneously, the liquid crystal phase-shifting structure, through phase-shifting electrodes, applies a bias voltage to alter the effective dielectric constant of the liquid crystal material, enabling continuous modulation of the RF signal phase. This effectively solves the technical problems of existing "split-type" solutions, where the signal from the chip pad to the radiating element requires multiple transitions, resulting in a longer path, increased parasitic parameters, and consequently, high-frequency signal loss and phase deviation. It achieves the technical effects of shortening the interconnect distance, reducing the number of transitions, lowering parasitic capacitance and inductance, and reducing high-frequency loss and phase deviation, thus ensuring beam pointing accuracy. This invention integrates the antenna radiating unit, feed network, liquid crystal phase-shifting structure, and multilayer flexible liquid crystal polymer substrate through a multilayer lamination process. The radio frequency chip is embedded in the chip embedding cavity inside the substrate, and the radio frequency connection between the components is achieved by replacing gold wire bonding with a vertical interconnect structure. This integrates the assembly process, which was originally divided into multiple independent processes, into an integrated lamination process. It effectively solves the technical problems of post-installation of phase shifter modules in existing "split" solutions, where the processing technology of phase shifter modules is independent of the substrate lamination process, there are many assembly steps, and even small changes in bonding parameters can cause performance disturbances. This invention achieves the technical effects of reducing assembly and mounting steps, eliminating the influence of bonding process parameter disturbances, and reducing process complexity, which is conducive to improving product consistency and manufacturing yield. Before the lamination process, this invention processes the bending curvature data of the flexible substrate and the exposed interconnection location data of the split structure using a support vector machine model to predict the mechanical stress distribution and extract the fracture risk area. Then, the random forest algorithm is used to perform phase compensation and electromagnetic simulation iterative optimization on the phase-shifting functional nodes, realizing a closed-loop layout optimization process from mechanical analysis to electromagnetic optimization. This effectively solves the problem that existing layout design methods cannot perform stress analysis and phase compensation for flexible substrate bending scenarios, ensuring the electrical performance and mechanical reliability of the integrated antenna from the design source. Attached Figure Description

[0011] To better understand and implement this application, the technical solution is described in detail below with reference to the accompanying drawings.

[0012] Figure 1 This is a schematic diagram of a conformal phased array antenna based on a flexible liquid crystal substrate, provided in Embodiment 1 of this application; Figure 2 This is a schematic flowchart illustrating a method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate, as provided in Embodiment 2 of this application. Detailed Implementation

[0013] To further illustrate the technical means and effects adopted by the present invention to achieve its intended purpose, exemplary embodiments will be described in detail below, examples of which are illustrated in the accompanying drawings. In the following description, when referring to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application.

[0014] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used herein are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any and all possible combinations of one or more of the associated listed items.

[0015] The following detailed description of the specific implementation methods, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided in detail.

[0016] Example 1, please refer to Figure 1 This embodiment provides a conformal phased array antenna based on a flexible liquid crystal substrate, including: A multilayer flexible liquid crystal polymer substrate includes at least two laminated liquid crystal polymer dielectric layers; the multilayer flexible liquid crystal polymer substrate has a predetermined thickness and a predetermined bending radius. Specifically, the thickness of the multilayer flexible liquid crystal polymer substrate is 0.1mm to 1.0mm; the bending radius of the multilayer flexible liquid crystal polymer substrate is determined according to its thickness, the ratio of bending radius to thickness is not less than 10:1, and the bending fatigue life of the multilayer flexible liquid crystal polymer substrate under the bending radius meets the requirement of more than 100,000 bending cycles; so as to adapt to the conformal bonding requirements of different curvature surfaces such as aircraft skin, cylindrical carriers and wearable devices.

[0017] The liquid crystal polymer dielectric layer is made of a liquid crystal polymer film, which has a stable dielectric constant and low loss characteristics in the microwave to millimeter wave frequency band. Its water absorption rate is 0.01% to 0.04%, and it can maintain stable radio frequency performance under antenna bending and humid and hot environments.

[0018] An antenna radiating element is disposed on the outermost surface of the multilayer flexible liquid crystal polymer substrate; the antenna radiating element is a microstrip patch antenna or a dipole antenna, and the antenna radiating elements are arranged in an array on the outermost surface of the multilayer flexible liquid crystal polymer substrate. Specifically, the operating frequency band of the antenna radiating element covers the microwave to millimeter wave frequency band. The array size is determined according to the actual beam scanning range and gain requirements. Each antenna radiating element is arranged on the substrate surface according to the equal spacing rule, and the spacing between adjacent elements is determined according to the wavelength corresponding to the operating frequency band.

[0019] A feeding network is disposed within the internal interlayer of the multilayer flexible liquid crystal polymer substrate. The feeding network is a microstrip line, stripline, or coplanar waveguide structure. Interlayer signal transmission between the feeding network and the antenna radiating elements is achieved through the vertical interconnect structure. The feeding network employs an equal-amplitude, equal-phase, or amplitude-weighted allocation method to distribute one input signal to multiple output channels and to distribute radio frequency signals to each antenna radiating element. The feed points of the antenna radiating elements are connected one-to-one with the vertical interconnect structure, thereby achieving a vertical transition from the internal traces to the surface antenna elements.

[0020] The liquid crystal phase-shifting structure is an integral structure with the multilayer flexible liquid crystal polymer substrate. The liquid crystal phase-shifting structure includes a liquid crystal material receiving cavity located inside the multilayer flexible liquid crystal polymer substrate, a phase-shifting electrode pair disposed on the inner wall of the liquid crystal material receiving cavity, and liquid crystal material filling the liquid crystal material receiving cavity. The liquid crystal phase-shifting structure changes the effective dielectric constant of the liquid crystal material by applying a bias voltage to the phase-shifting electrode pair, thereby realizing continuous modulation of the phase of the radio frequency signal.

[0021] The liquid crystal material receiving cavity is located in the inner interlayer of the multilayer flexible liquid crystal polymer substrate. The upper and lower inner walls of the liquid crystal material receiving cavity are respectively provided with the upper electrode and the lower electrode of the phase-shifting electrode pair, and the upper electrode and the lower electrode are spaced apart by a preset distance. The liquid crystal material receiving cavity is surrounded by a sealing adhesive wall, which seals the liquid crystal material in the liquid crystal material receiving cavity. The upper electrode and the lower electrode of the phase-shifting electrode pair are electrically connected to the bias voltage output terminal of the embedded radio frequency chip through the vertical interconnect structure, so that the radio frequency chip can directly control the bias voltage of each phase-shifting unit.

[0022] The distance between the upper electrode and the lower electrode is 50μm to 200μm, preferably 100μm. The liquid crystal material is a filamentary phase liquid crystal with a dielectric anisotropy Δε ≥ 2.5. Within a bias voltage range of 0 to 30V, the director of the liquid crystal molecules gradually turns parallel to the electric field direction as the electric field strength increases. The effective dielectric constant of the liquid crystal layer continuously changes from ε∥ (parallel to the direction of the molecular long axis) to ε⊥ (perpendicular to the direction of the molecular long axis), thereby realizing a continuous delay in the phase of microwave signal transmission. The liquid crystal material cavity is located on the signal transmission path between the feed network and the antenna radiating element. When the radio frequency signal is transmitted through the liquid crystal layer in the liquid crystal material cavity, its phase change Δφ satisfies Δφ = (2π / λ)·Δn·d, where λ is the operating wavelength, Δn is the dielectric anisotropy refractive index difference of the liquid crystal material, and d is the effective thickness of the liquid crystal layer, thereby realizing the phase shifting function.

[0023] An embedded radio frequency (RF) chip is placed in a chip embedding cavity inside the multilayer flexible liquid crystal polymer substrate. The embedded RF chip integrates at least an RF signal amplification function and also integrates a control function for applying the bias voltage to the liquid crystal phase-shifting structure.

[0024] Specifically, the embedded radio frequency chip includes a low-noise amplifier and a power amplifier connected in sequence; the signal input terminal of the low-noise amplifier is connected to the signal receiving terminal of the antenna radiating element through the vertical interconnect structure to form a signal receiving link, which is used to amplify the weak signal received by the antenna with low noise; the signal output terminal of the power amplifier is connected to the signal input terminal of the feed network through the vertical interconnect structure to form a signal transmitting link, which is used to amplify the signal to be transmitted to the required power level before feeding it into the feed network.

[0025] The embedded radio frequency chip also integrates a bias voltage generating circuit. The output terminal of the bias voltage generating circuit is electrically connected to the phase-shifting electrode through the vertical interconnect structure. The bias voltage output by the bias voltage generating circuit is a preset bias voltage value. Specifically, the bias voltage output by the bias voltage generating circuit is in the range of 0 to 30V. Within this bias voltage range, the liquid crystal phase-shifting structure can achieve continuous phase modulation from 0° to 360°.

[0026] The depth of the chip embedding cavity is greater than the thickness of the embedded RF chip, ensuring that the chip is completely embedded inside the substrate without being exposed. A thermally conductive copper foil layer is provided at the bottom of the chip embedding cavity. The thermally conductive copper foil layer is thermally connected to the ground layer of the multilayer flexible liquid crystal polymer substrate to quickly dissipate the heat generated during the operation of the RF chip, ensuring that the chip operates stably within the rated temperature range.

[0027] The thermally conductive copper foil layer has a thickness of 10μm to 35μm. It is formed at the bottom of the chip embedding cavity by electroplating and is thermally connected to the ground layer through an array of thermally conductive vias inside the substrate. The vias have a diameter of 100μm to 200μm and are plated with a copper layer on their inner walls. The number of vias is determined according to the chip power consumption, with no less than 4 vias per watt of power consumption to ensure that the junction temperature of the chip does not exceed 125°C during operation.

[0028] A vertical interconnect structure is disposed inside the multilayer flexible liquid crystal polymer substrate. The vertical interconnect structure is a metallized blind via, a buried via, or a copper paste interconnect structure. The vertical interconnect structure has a preset aperture. Specifically, the aperture of the vertical interconnect structure is 75μm to 200μm, preferably 100μm to 150μm. The inner wall of the vertical interconnect structure is plated with a copper layer to achieve a low-resistance signal transmission path. The vertical interconnect structure is fabricated by laser drilling, chemical copper plating, and electroplating copper filling processes. It is used to realize the vertical transmission of radio frequency signals and control signals between different layers within a multilayer liquid crystal polymer substrate, effectively shortening the interconnect distance, reducing signal delay, and reducing parasitic inductance and parasitic capacitance.

[0029] In the vertical interconnect structure, metallized blind vias are used to connect the pads of the RF chip to the signal lines of the feed network, metallized buried vias are used to connect the feed network traces between different layers, and copper paste interconnect structures are used to fill large-diameter vias to achieve low-impedance grounding connections. The drilling position of the metallized blind vias is aligned with the chip pads using a laser direct imaging (LDI) alignment system with an alignment accuracy of ±15μm. The ratio of the hole bottom diameter to the chip pad diameter is 1:1.2 to ensure that the bottom of the metallized blind via completely covers the chip pad. The copper layer thickness of the hole wall of the metallized blind via is 5μm to 25μm, and the copper layer thickness at the bottom of the hole is not less than 10μm to ensure reliable electrical contact between the bottom of the blind via and the chip pad.

[0030] The antenna radiating element, the feeding network, the liquid crystal phase-shifting structure, and the multilayer flexible liquid crystal polymer substrate are integrally formed by a multilayer lamination process.

[0031] The multilayer lamination process is carried out in a vacuum hot press at a lamination temperature of 200℃~220℃, a holding time of more than 60 minutes, and a lamination pressure of 2MPa~5MPa. This process causes each liquid crystal polymer dielectric layer to undergo plastic deformation in a molten state and bond tightly together. After lamination, annealing is performed immediately at a temperature of 150℃ for 1 hour to eliminate residual stress between layers and ensure that the substrate meets the bending fatigue life requirement of more than 100,000 bends.

[0032] The embedded radio frequency chip is connected to the feed network via the vertical interconnect structure, and the feed network is connected to the antenna radiating unit via the liquid crystal phase shift structure, forming a complete signal transmission link and signal reception link.

[0033] The embedded radio frequency chip is also electrically connected to the phase-shifting electrode through the vertical interconnect structure to apply the bias voltage to the liquid crystal phase-shifting structure, thereby enabling the radio frequency chip to independently control the phase of each antenna unit, and thus achieve rapid beam scanning and precise pointing.

[0034] The specific implementation method of this embodiment is as follows: First, a multilayer flexible liquid crystal polymer substrate is provided, and the thickness and stacking order of each liquid crystal polymer dielectric layer are determined according to the target operating frequency band; then, an antenna radiating element array is prepared on the outermost surface by thin film processes such as photolithography, sputtering, and electroplating, and a conductive pattern of the feed network is prepared between the inner layers; a liquid crystal material receiving cavity is formed inside the substrate by laser processing or plasma etching, and a phase-shifting electrode pair is prepared on the upper and lower inner walls of the receiving cavity by sputtering or electroplating; after vacuum injection of liquid crystal material, it is sealed by dispensing. A chip embedding cavity is formed inside the substrate by laser opening. After the radio frequency chip is mounted into the cavity by a pick-and-place device, the substrate layers are stacked in a preset order and placed in a vacuum hot press for lamination. The lamination temperature is controlled at 200℃~220℃, the pressure is 2MPa~5MPa, and the heat is held for more than 60 minutes. This allows the liquid crystal polymer dielectric layers to be shaped and deformed in a molten state and tightly bonded together. At the same time, the chip is completely wrapped inside the substrate to form an embedded packaging structure. After lamination, blind vias are formed at corresponding positions on the substrate surface using laser drilling. Vertical interconnect structures are then formed through chemical copper plating and electroplating. The input and output pads of the RF chip are electrically connected to the signal lines of the feed network, the lead-out pads of the phase-shifting electrode pairs, and the feed points of the antenna radiating element, respectively. Finally, the transmitted signal generated by the RF chip is amplified by a power amplifier and transmitted to the feed network through the vertical interconnect structure. The feed network distributes the signal to each liquid crystal phase-shifting structure for phase modulation. The phase-modulated signal is then transmitted to the antenna radiating element for outward radiation through the vertical interconnect structure. During reception, the signal received by the antenna radiating element is transmitted to the liquid crystal phase-shifting structure via the vertical interconnect structure for phase modulation, and then synthesized by the feed network before being transmitted to the low-noise amplifier of the RF chip via the vertical interconnect structure for amplification. The bias voltage generation circuit integrated inside the RF chip applies the corresponding bias voltage to each phase-shifting electrode pair through the vertical interconnect structure, changing the effective dielectric constant of the liquid crystal material, thereby realizing independent and continuous phase modulation of each antenna element, and thus achieving rapid beam scanning and precise pointing.

[0035] Example 2, as Figure 2As shown, a method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate, used to fabricate the conformal phased array antenna based on a flexible liquid crystal substrate, includes the following steps: S1. A multilayer flexible liquid crystal polymer substrate is provided, wherein the multilayer flexible liquid crystal polymer substrate includes at least two liquid crystal polymer dielectric layers; Specifically, the liquid crystal polymer dielectric layer is a liquid crystal polymer film, which exhibits a stable dielectric constant and low loss characteristics in the microwave to millimeter-wave frequency band, with a water absorption rate of 0.01% to 0.04%. The multilayer flexible liquid crystal polymer substrate has a thickness of 0.1 mm to 1.0 mm and a bending radius of 5 mm to 50 mm, adaptable to conformal bonding requirements of surfaces with different curvatures, such as aircraft skins, cylindrical carriers, and wearable devices. The provided liquid crystal polymer dielectric layer undergoes cleaning and plasma surface treatment before use to improve interlayer bonding and adhesion between each functional layer and the substrate.

[0036] S2. Conductive patterns of antenna radiating elements and feed networks are prepared on at least one layer of the liquid crystal polymer dielectric layer; Specifically, the conductive pattern is fabricated using a thin-film process, including the following sub-steps: forming a metal seed layer on the surface of the liquid crystal polymer dielectric layer by sputtering or chemical plating; coating photoresist on the metal seed layer, and forming a conductive pattern mask by exposure and development; depositing a conductive metal layer in the opening area of ​​the mask by electroplating to thicken the conductive pattern to a preset thickness; removing the photoresist and etching to remove the exposed metal seed layer to obtain the final conductive pattern. The conductive pattern of the feed network is fabricated in the inner interlayer of the multilayer flexible liquid crystal polymer substrate, and the conductive pattern of the antenna radiating element is fabricated on the outermost surface of the multilayer flexible liquid crystal polymer substrate. The conductive pattern uses copper as the conductive material, and the thickness of the conductive pattern is 5μm to 35μm. The linewidth and line spacing are determined according to the operating frequency band and characteristic impedance requirements.

[0037] S3. A liquid crystal phase-shifting structure is prepared inside the multilayer flexible liquid crystal polymer substrate, specifically including: forming a liquid crystal material receiving cavity in the liquid crystal polymer dielectric layer, preparing a phase-shifting electrode pair on the inner wall of the liquid crystal material receiving cavity, filling the liquid crystal material receiving cavity with liquid crystal material, and sealing the liquid crystal material receiving cavity around its perimeter. More specifically, the method for forming the liquid crystal material receiving cavity in the liquid crystal polymer dielectric layer is as follows: a groove structure is formed on at least one layer of the liquid crystal polymer dielectric layer by laser processing or plasma etching, the depth and area of ​​the groove structure being determined according to the required phase shift amount; the phase shifting electrode pair is prepared on the inner wall of the groove structure by sputtering or electroplating, the phase shifting electrode pair including an upper electrode and a lower electrode arranged opposite each other, the electrode material being gold or copper, and the electrode thickness being 0.1μm to 1μm; the liquid crystal material is injected into the groove structure, the liquid crystal material being nematic liquid crystal or smectic liquid crystal, having high dielectric anisotropy and low loss characteristics, and is filled by vacuum injection to ensure that the liquid crystal material fully fills the receiving cavity without air bubbles remaining; a sealing wall is formed around the groove structure by dispensing or printing, the sealing wall being epoxy resin or UV-curable adhesive, sealing the liquid crystal material within the liquid crystal material receiving cavity. The width of the sealing wall is 0.5mm to 2mm, and after curing, the sealing wall forms an airtight sealing structure to prevent liquid crystal material leakage and the intrusion of external impurities.

[0038] S4. A chip embedding cavity is prepared inside the multilayer flexible liquid crystal polymer substrate; Specifically, the chip embedding cavity is processed by laser drilling or mechanical milling before lamination. When using laser drilling, an ultraviolet laser or a carbon dioxide laser is used to create cavities layer by layer on the liquid crystal polymer dielectric layer. The laser processing accuracy is ±25μm. The cavity size matches the size of the RF chip to be embedded, and the cavity depth is 0.05mm to 0.2mm greater than the thickness of the RF chip to reserve space for chip embedding. A thermally conductive copper foil is provided at the bottom of the chip embedding cavity for heat dissipation of the RF chip. The thermally conductive copper foil is formed at the bottom of the chip embedding cavity by electroplating or lamination, and its thickness is 10μm to 35μm. The thermally conductive copper foil is thermally connected to the ground layer of the multilayer flexible liquid crystal polymer substrate to form a thermally conductive path.

[0039] S5. Embed the radio frequency chip in the chip embedding cavity. The radio frequency chip integrates at least radio frequency signal amplification function and control function for applying bias voltage to the liquid crystal phase shifting structure. Specifically, the RF chip includes a low-noise amplifier and a power amplifier connected in sequence. The low-noise amplifier amplifies the weak signal received by the antenna with low noise, and the power amplifier amplifies the signal to be transmitted to the required power level. The RF chip also integrates a bias voltage generation circuit, the bias voltage output of which has a range of 0–30V. The RF chip is placed in a chip embedding cavity with a placement accuracy of ±25μm using a pick-and-place device, with the chip's input and output pads facing upwards. The chip is fixed to the bottom of the chip embedding cavity using an adhesive material, which is either thermally conductive and conductive or non-conductive, with a thickness controlled between 10μm and 50μm to ensure good thermal contact between the chip and the thermally conductive copper foil at the bottom of the cavity. After the chip is embedded, a bottom-filling process is used to fill the space between the chip and the cavity sidewall with bottom filler adhesive to reduce thermal mismatch stress.

[0040] The bias voltage generating circuit is a boost DC-DC converter or a charge pump circuit, with an input voltage of 1.8V or 3.3V (from the system power supply) and an output voltage adjustable in 0.1V steps within the range of 0 to 30V. The bias voltage generating circuit has a built-in digital-to-analog converter (DAC). The embedded RF chip writes voltage control words to the DAC via an internal bus. The DAC converts the digital control words into corresponding analog voltages and outputs them to the phase-shifting electrode pairs, thereby achieving independent and precise control of the bias voltage of each liquid crystal phase-shifting unit.

[0041] S6. The liquid crystal polymer dielectric layers are laminated and pressed together by a lamination process, so that the antenna radiating unit, the feed network, the liquid crystal phase shifting structure and the multilayer flexible liquid crystal polymer substrate are integrally formed. Specifically, the liquid crystal polymer dielectric layers that have completed pattern preparation are stacked in a preset order and placed in a vacuum hot press for lamination. The lamination process is carried out at a preset lamination temperature for a preset holding time, and at a preset lamination pressure.

[0042] More specifically, the lamination process is carried out at a temperature of 200℃~220℃, with a holding time of more than 60 minutes and a lamination pressure of 2MPa~5MPa. During the lamination process, each liquid crystal polymer dielectric layer undergoes plastic deformation in a molten state, the interlayer interface disappears, and they are tightly bonded together. After lamination, an annealing treatment is performed at a temperature of 150℃ for 1 hour to eliminate residual stress between layers, ensuring that the substrate's bending fatigue life meets the requirement of more than 100,000 bends. The chip is uniformly wrapped by each substrate layer during the lamination process, forming an embedded packaging structure that does not require an additional sealing cover.

[0043] S7. A vertical interconnect structure is prepared inside the multilayer flexible liquid crystal polymer substrate, wherein the vertical interconnect structure is a metallized blind via, a buried via, or a copper paste interconnect structure. Specifically, the vertical interconnect structure is fabricated as follows: blind holes or through holes are formed on the liquid crystal polymer dielectric layer by laser drilling. The laser drilling uses an ultraviolet laser or a CO2 laser, and the hole diameter is 50μm to 200μm. A copper layer is deposited on the inner wall of the blind holes or through holes by chemical plating or electroplating, and the copper layer thickness is 5μm to 25μm. The blind holes or through holes are filled with conductive paste to form a copper paste interconnect structure. The vertical interconnect structure is used to realize the vertical electrical connection between the RF chip pads, the feed network, and the phase-shifting electrode pairs, so that the signal transmission direction changes from horizontal wiring to a vertically penetrating low parasitic path. When fabricating the vertical interconnect structure, a laser is used to form microholes inside the substrate, and the hole walls are metallized by chemical copper deposition, electroplating, and other processes, thereby realizing electrical conduction between the upper and lower layers.

[0044] S8. The RF chip is connected to the feed network via the vertical interconnect structure, the feed network is connected to the antenna radiating unit via the liquid crystal phase-shifting structure, and the RF chip is electrically connected to the phase-shifting electrode via the vertical interconnect structure to apply the bias voltage to the liquid crystal phase-shifting structure.

[0045] Specifically, one end of the vertical interconnect structure is connected to the input / output pads of the RF chip, and the other end is connected to the signal line of the feed network or the lead-out pads of the phase-shifting electrode pair, thus realizing a complete RF signal link. In the signal transmission link, the RF signal output by the power amplifier of the RF chip is transmitted to the feed network via the vertical interconnect structure. The feed network distributes the signal to each liquid crystal phase-shifting structure for phase modulation. The phase-modulated signal is then transmitted to the antenna radiating element for outward radiation via the vertical interconnect structure. In the signal reception link, the signal received by the antenna radiating element is transmitted to the liquid crystal phase-shifting structure via the vertical interconnect structure for phase modulation. After being synthesized by the feed network, it is transmitted to the low-noise amplifier of the RF chip via the vertical interconnect structure for amplification. The bias voltage output by the bias voltage generation circuit of the RF chip is transmitted to the phase-shifting electrode pair via the vertical interconnect structure. By adjusting the bias voltage value, the effective dielectric constant of the liquid crystal material is changed, thereby realizing continuous modulation of the RF signal phase.

[0046] Furthermore, prior to the lamination process, a layout optimization step is also included: The bending curvature data of the flexible substrate and the exposed interconnection position data of the split structure are obtained. The bending curvature data and the exposed interconnection position data are processed by the support vector machine model to obtain the mechanical stress distribution map. Specifically, the bending curvature data includes the radius of curvature data of various regions on different carrier surfaces (such as aircraft skin, cylindrical carriers, and wearable device bonding surfaces) of the flexible substrate, and the exposed interconnection location data includes the coordinates and distribution density data of the gold wire bonding points. The support vector machine model uses a radial basis function for regression prediction, taking the bending curvature data and exposed interconnection location data as input features, and outputs the predicted mechanical stress values ​​at each coordinate position, thereby generating a stress distribution map of the entire board.

[0047] Based on the mechanical stress distribution map, structural fracture risk areas with stress values ​​greater than a preset threshold are extracted, and the coordinates of signal transfer nodes within the structural fracture risk areas are obtained. The preset threshold is the 80th percentile of the stress values ​​in the mechanical stress distribution map. That is, the 80th percentile of all stress values ​​in the stress distribution map is taken as the judgment threshold. Areas above the threshold are judged as structural fracture risk areas. The coordinates of the signal transfer node are specifically the location coordinates of the gold wire bonding pads or module mounting solder joints. These nodes are the location of the bonding interface in the split structure, and the stress concentration is most significant in the bending state.

[0048] For the coordinates of the signal transfer node, the corresponding initial high-frequency signal loss value and initial phase deviation value are obtained. If the initial high-frequency signal loss value is greater than a preset loss threshold, the topology of the coordinates of the signal transfer node is reconstructed to obtain an integrated cabling path. The preset loss threshold is -3dB, meaning that when the insertion loss of a signal transfer node is greater than -3dB, the signal transmission performance of that node is deemed to fail to meet the performance requirements. The topology reconstruction specifically includes replacing the gold wire bonding connection at the coordinates of the signal transfer node with a vertical interconnect structure connection, changing the signal transmission path from multi-segment transitions to a single-segment continuity, and eliminating all bonding interfaces within the structural fracture risk area. In the integrally molded wiring path, signal connections between functional units are achieved through wiring and vertical interconnect structures within the substrate, with no exposed bonding interfaces.

[0049] The phase-shifting functional nodes on the integrally formed wiring path are obtained, and the phase-shifting functional nodes and the initial phase deviation value are extracted using the random forest algorithm to obtain the phase compensation control sequence. Specifically, the features extracted by the random forest algorithm include the position coordinates of the phase-shifting functional nodes, the relative distance between the phase-shifting functional nodes and the signal transfer nodes, and the distribution characteristics of the initial phase deviation values; the phase compensation control sequence includes the compensation phase values ​​of each phase-shifting functional node. The random forest model establishes a nonlinear mapping relationship between input features and phase compensation values ​​through ensemble learning of multiple decision trees, and outputs the preliminary compensation phase for each node.

[0050] According to the phase compensation control sequence, electromagnetic simulation is performed on the integrally formed wiring path to obtain the simulated beam pointing angle. The electromagnetic simulation uses three-dimensional full-wave electromagnetic field simulation software to establish an antenna array full-wave simulation model that includes substrate material parameters, conductor parameters and liquid crystal phase shift structure electromagnetic model. The phase compensation control sequence is input into the simulation model to obtain the beam pointing angle of the antenna array in the far field.

[0051] The difference between the simulated beam pointing angle and the target beam pointing angle is determined. If the difference is greater than a preset angle threshold, the phase compensation control sequence is iteratively updated to obtain the target phase compensation control sequence. The preset angle threshold is 2°. When the difference is greater than 2°, the difference is used as a feedback signal, and the compensation phase value of each phase-shifting functional node in the phase compensation control sequence is adjusted using the gradient descent method. Then, electromagnetic simulation verification is performed again, and this process is repeated iteratively until the difference is less than or equal to 2°. The number of iterations does not exceed 50. If the difference still does not converge to within the threshold after 50 iterations, the phase compensation control sequence corresponding to the minimum difference is output as the result.

[0052] The target phase compensation control sequence is used to virtually eliminate the bonding interface corresponding to the integrally formed wiring path to determine the integrally formed layout of the target flexible phased array antenna. Specifically, the virtual elimination process involves deleting all gold wire bonding pads and module mounting solder joints within the structural fracture risk area in the layout design file, replacing the original bonding interface connection relationship with the connection relationship of the vertical interconnect structure, and writing the target phase compensation control sequence into the control parameters of each phase shifting functional node in the layout file to form the final integrally molded layout for physical fabrication.

[0053] The lamination process is performed according to the integral molding pattern.

[0054] The lamination process involves preparing the conductive patterns, cavity structures, and vertical interconnect positions of each liquid crystal polymer dielectric layer according to the integrated molding layout after layout optimization. This ensures that the layout optimization results are fully realized in the physical fabrication stage. Through the organic combination of layout optimization and physical fabrication, the resulting integrated flexible phased array antenna eliminates all exposed bonding interfaces, and the signal transmission path is a fully through path inside the substrate. The phase accuracy is guaranteed through AI optimization, meeting the mechanical reliability and electrical performance requirements in the case of conformal curved surfaces of flexible substrates.

[0055] The specific implementation method of this embodiment is as follows: First, a multilayer LCP substrate is provided. After the surface is activated by plasma treatment, conductive patterns of antenna radiating elements and feed networks are prepared on the corresponding layers using thin film technology. Grooves are formed inside the substrate by laser processing. Phase-shifting electrode pairs are sputtered on the inner wall of the grooves. After vacuum injection of liquid crystal material, adhesive is applied to seal and form a liquid crystal phase-shifting structure. Chip embedding cavities are formed inside the substrate by laser cavity opening. Radio frequency chips are mounted into the cavity and fixed by pick-and-place equipment. A protective film is covered on top of the chip. The substrate layers are stacked in a preset order and placed in a vacuum hot press for lamination, so that the substrate layers are fused together as one and the chip is embedded inside the substrate. After lamination, the chip pad positions are identified using an X-ray alignment system, and blind holes are drilled at the corresponding positions using a UV laser. A vertical interconnect structure is formed by chemical plating and electroplating to fill copper, connecting the RF chip to the power supply network, liquid crystal phase-shifting structure, and antenna radiating unit. Finally, the electrical performance and mechanical reliability are verified through finished product testing.

[0056] This method integrates multiple independent processes, originally belonging to mounting, bonding, and packaging, into a unified lamination process. During the lamination process, the chip is uniformly wrapped by the substrate material to form an embedded package. The vertical interconnect structure replaces the gold wire bonding to achieve full internal interconnection between the chip and the substrate, thereby eliminating the exposed bonding interface and avoiding the stress fracture problem of bonding points in curved conformal scenarios. At the same time, it shortens the signal transmission path, reduces parasitic parameters, and ensures high-frequency transmission performance and beam pointing accuracy.

[0057] Furthermore, this invention includes a layout optimization step before the S6 lamination step. It uses a support vector machine model to predict the mechanical stress distribution and extract fracture risk areas. It replaces the bonding interfaces in the risk areas with vertical interconnect structures through topology reconstruction and uses a random forest algorithm for phase compensation and electromagnetic simulation iterative optimization to ensure that the final integral molded layout meets the design requirements in terms of both mechanical stress and phase accuracy. This makes the layout optimization and physical fabrication form a complete closed-loop process.

[0058] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any brief modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A conformal phased array antenna based on a flexible liquid crystal substrate, characterized in that: include: A multilayer flexible liquid crystal polymer substrate, comprising at least two laminated liquid crystal polymer dielectric layers; An antenna radiating element is disposed on the outermost surface of the multilayer flexible liquid crystal polymer substrate; A power supply network is disposed between the internal layers of the multilayer flexible liquid crystal polymer substrate; The liquid crystal phase-shifting structure is an integral structure with the multilayer flexible liquid crystal polymer substrate. The liquid crystal phase-shifting structure includes a liquid crystal material receiving cavity located inside the multilayer flexible liquid crystal polymer substrate, a pair of phase-shifting electrodes disposed on the inner wall of the liquid crystal material receiving cavity, and liquid crystal material filling the liquid crystal material receiving cavity. The liquid crystal phase-shifting structure changes the effective dielectric constant of the liquid crystal material by applying a bias voltage to the pair of phase-shifting electrodes, thereby realizing continuous modulation of the phase of the radio frequency signal. An embedded radio frequency chip is embedded in a chip embedding cavity inside the multilayer flexible liquid crystal polymer substrate. The embedded radio frequency chip integrates at least radio frequency signal amplification function, and the embedded radio frequency chip also integrates control function for applying the bias voltage to the liquid crystal phase shifting structure. A vertical interconnect structure is disposed inside the multilayer flexible liquid crystal polymer substrate, wherein the vertical interconnect structure is a metallized blind via, a buried via, or a copper paste interconnect structure. The antenna radiating element, the feeding network, the liquid crystal phase-shifting structure, and the multilayer flexible liquid crystal polymer substrate are integrally formed by a multilayer lamination process. The embedded radio frequency chip is connected to the feed network via the vertical interconnect structure, and the feed network is connected to the antenna radiating unit via the liquid crystal phase shift structure. The embedded radio frequency chip is also electrically connected to the phase-shifting electrode through the vertical interconnect structure to apply the bias voltage to the liquid crystal phase-shifting structure.

2. The conformal phased array antenna based on a flexible liquid crystal substrate according to claim 1, characterized in that: The liquid crystal material receiving cavity is located between the inner layers of the multilayer flexible liquid crystal polymer substrate. The upper and lower inner walls of the liquid crystal material receiving cavity are respectively provided with the upper electrode and the lower electrode of the phase-shifting electrode pair, and the upper electrode and the lower electrode are spaced apart by a preset distance. A sealing wall is provided around the liquid crystal material receiving cavity, and the sealing wall seals the liquid crystal material inside the liquid crystal material receiving cavity; The upper and lower electrodes of the phase-shifting electrode pair are electrically connected to the bias voltage output terminal of the embedded radio frequency chip through the vertical interconnect structure.

3. The conformal phased array antenna based on a flexible liquid crystal substrate according to claim 1, characterized in that: The embedded radio frequency chip includes a low-noise amplifier and a power amplifier connected in sequence. The signal input terminal of the low-noise amplifier is connected to the signal receiving terminal of the antenna radiating element through the vertical interconnection structure, forming a signal receiving link. The signal output terminal of the power amplifier is connected to the signal input terminal of the power supply network through the vertical interconnection structure, forming a signal transmission link; The embedded radio frequency chip also integrates a bias voltage generating circuit. The output terminal of the bias voltage generating circuit is electrically connected to the phase-shifting electrode through the vertical interconnect structure. The bias voltage output by the bias voltage generating circuit is a preset bias voltage value.

4. A conformal phased array antenna based on a flexible liquid crystal substrate according to claim 1, characterized in that: The antenna radiating element is a microstrip patch antenna or a dipole antenna, and the antenna radiating element is arranged in an array on the outermost surface of the multilayer flexible liquid crystal polymer substrate. The feed network is a microstrip line, stripline, or coplanar waveguide structure, and the feed network and the antenna radiating element are connected by the vertical interconnection structure to achieve interlayer signal transmission. The feed points of the antenna radiating elements are connected one-to-one with the vertical interconnection structure.

5. A conformal phased array antenna based on a flexible liquid crystal substrate according to claim 1, characterized in that: The multilayer flexible liquid crystal polymer substrate has a preset thickness and a preset bending radius. The depth of the chip embedding cavity is greater than the thickness of the embedded radio frequency chip. A thermally conductive copper foil layer is provided at the bottom of the chip embedding cavity, and the thermally conductive copper foil layer is thermally connected to the ground layer of the multilayer flexible liquid crystal polymer substrate. The vertical interconnect structure has a preset aperture, and the inner wall of the vertical interconnect structure is plated with a copper layer.

6. A method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate, used to fabricate the conformal phased array antenna based on a flexible liquid crystal substrate as described in any one of claims 1-5, characterized in that, Includes the following steps: S1. A multilayer flexible liquid crystal polymer substrate is provided, wherein the multilayer flexible liquid crystal polymer substrate includes at least two liquid crystal polymer dielectric layers; S2. Conductive patterns of antenna radiating elements and feed networks are prepared on at least one layer of the liquid crystal polymer dielectric layer; S3. A liquid crystal phase-shifting structure is prepared inside the multilayer flexible liquid crystal polymer substrate, specifically including: forming a liquid crystal material receiving cavity in the liquid crystal polymer dielectric layer, preparing a phase-shifting electrode pair on the inner wall of the liquid crystal material receiving cavity, filling the liquid crystal material receiving cavity with liquid crystal material, and sealing the liquid crystal material receiving cavity around its perimeter. S4. A chip embedding cavity is prepared inside the multilayer flexible liquid crystal polymer substrate; S5. Embed the radio frequency chip in the chip embedding cavity. The radio frequency chip integrates at least radio frequency signal amplification function and control function for applying bias voltage to the liquid crystal phase shifting structure. S6. The liquid crystal polymer dielectric layers are laminated and pressed together by a lamination process, so that the antenna radiating unit, the feed network, the liquid crystal phase shifting structure and the multilayer flexible liquid crystal polymer substrate are integrally formed. S7. A vertical interconnect structure is prepared inside the multilayer flexible liquid crystal polymer substrate, wherein the vertical interconnect structure is a metallized blind via, a buried via, or a copper paste interconnect structure. S8. The RF chip is connected to the feed network via the vertical interconnect structure, the feed network is connected to the antenna radiating unit via the liquid crystal phase-shifting structure, and the RF chip is electrically connected to the phase-shifting electrode via the vertical interconnect structure to apply the bias voltage to the liquid crystal phase-shifting structure.

7. The method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate according to claim 6, characterized in that: The lamination process is carried out at a preset lamination temperature and for a preset heat preservation time, and the lamination process is carried out under a preset lamination pressure. The chip embedding cavity is processed by laser drilling or mechanical milling before lamination; The bottom of the chip embedding cavity is provided with a thermally conductive copper foil for heat dissipation of the radio frequency chip.

8. The method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate according to claim 6, characterized in that: The specific method for forming the liquid crystal material receiving cavity in the liquid crystal polymer dielectric layer is as follows: A groove structure is formed on at least one of the liquid crystal polymer dielectric layers by laser processing or plasma etching. The phase-shifting electrode pair is prepared on the inner wall of the groove structure by sputtering or electroplating. The liquid crystal material is injected into the groove structure; A sealing wall is formed around the groove structure by dispensing or printing to seal the liquid crystal material within the liquid crystal material receiving cavity.

9. The method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate according to claim 6, characterized in that: The vertical interconnect structure is fabricated as follows: Blind holes or through holes are formed on the liquid crystal polymer dielectric layer by laser drilling; A copper layer is deposited on the inner wall of the blind or through hole by chemical plating or electroplating. The blind or through holes are filled with conductive paste to form a copper paste interconnect structure.

10. The method for fabricating a conformal phased array antenna based on a flexible liquid crystal substrate according to claim 6, characterized in that: Prior to the lamination process, a layout optimization step is also included: The bending curvature data of the flexible substrate and the exposed interconnection position data of the split structure are obtained. The bending curvature data and the exposed interconnection position data are processed by the support vector machine model to obtain the mechanical stress distribution map. Based on the mechanical stress distribution map, structural fracture risk areas with stress values ​​greater than a preset threshold are extracted, and the coordinates of signal transfer nodes within the structural fracture risk areas are obtained. For the coordinates of the signal transfer node, the corresponding initial high-frequency signal loss value and initial phase deviation value are obtained. If the initial high-frequency signal loss value is greater than a preset loss threshold, the topology of the coordinates of the signal transfer node is reconstructed to obtain an integrated cabling path. The phase-shifting functional nodes on the integrally formed wiring path are obtained, and the phase-shifting functional nodes and the initial phase deviation value are extracted using the random forest algorithm to obtain the phase compensation control sequence. Electromagnetic simulation is performed on the integrally formed wiring path according to the phase compensation control sequence to obtain the simulated beam pointing angle; The difference between the simulated beam pointing angle and the target beam pointing angle is determined. If the difference is greater than a preset angle threshold, the phase compensation control sequence is iteratively updated to obtain the target phase compensation control sequence. The target phase compensation control sequence is used to virtually eliminate the bonding interface corresponding to the integrally formed wiring path to determine the integrally formed layout of the target flexible phased array antenna. The lamination process is performed according to the integral molding pattern.

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