Surface radar based on semi-flexible phased array antenna front end and manufacturing method thereof

Abstract

The application discloses a surface radar based on a semi-flexible phased array antenna front end and a manufacturing method thereof, and aims to solve the problems of low integration, poor curved surface adaptability, poor high-temperature protection and heat dissipation and complicated structure assembly of existing phased array radars. The surface radar comprises a wave-transparent heat protection layer, a phase change heat dissipation layer, a semi-flexible phased array antenna front end, a beam control circuit board and a flange, the antenna front end is fixed through a dielectric bolt and signal transmission is realized by means of an FPC flexible circuit, the phase change heat dissipation layer is filled with a phase change material in a built-in cavity, the semi-flexible phased array antenna front end is spliced by a plurality of subarray modules and a flexible packaging layer, and conforms to the conformal installation demand of different curvatures, the beam control circuit board receives a host computer control instruction and converts the host computer control instruction into an antenna driving control signal, and array beam regulation and control are realized. The application realizes the integrated integration of complex curved surface conformal installation, heat protection, phase change heat dissipation and array state monitoring, and effectively improves the complex working condition adaptability and working reliability of the radar.

Description

Technical Field

[0001] This invention belongs to the field of radar antenna technology, and further relates to an integrated surface radar structure that combines complex curved surface conformal installation, modular splicing, thermal protection, phase change heat dissipation and state perception functions. Specifically, it is a surface radar based on the front end of a semi-flexible phased array antenna and its manufacturing method. Background Technology

[0002] With the ever-increasing demands of modern electronic information systems for precise detection, anti-interference capabilities, and high-speed data transmission performance, phased array antennas, with their advantages of fast beam scanning speed, large power aperture product, ease of all-solid-state integration, and miniaturization, have been widely used in core fields such as radar, communication, navigation, and electronic warfare. They are currently key components for improving the overall performance of electronic equipment. Currently, most phased array antennas used in engineering employ rigid planar arrays or simple curved surface conformal structures, which can meet the basic electrical performance requirements in conventional scenarios. However, they still have significant technical shortcomings in areas such as adaptation to complex curved surfaces, high-temperature environment adaptability, integrated design, and reconfigurable assembly, making it difficult to meet the multi-scenario, high-reliability, and long-term stable operation requirements of next-generation high-end electronic equipment.

[0003] Existing technologies have developed related improvement schemes such as flexible phased arrays, semi-flexible packaged arrays, and assembly optimization processes, which have improved the flexibility and assembly accuracy of phased array antennas to a certain extent.

[0004] Existing typical flexible antenna solutions mostly adopt an integrated prefabricated structure, integrating the feed structure, power divider network, phase shifting module, and radiating element onto a single flexible substrate. This makes it difficult to achieve flexible conformal, modular splicing, and local deformation compensation for complex three-dimensional curved surfaces. For example, the patent document CN115483536B entitled "Flexible Phased Array Antenna and Fabrication Method" uses an LCP flexible substrate to achieve overall antenna integration, which can achieve small-amplitude flexible deformation and high-frequency low-loss transmission, meeting the needs of conventional flexible conformal applications. However, this solution mainly focuses on the integration of feed, power divider, phase shifting, and radiating elements on the flexible substrate, without adopting a modular subarray splicing architecture or setting flexible buffer connection structures between array elements. It cannot release the structural stress generated by large curvature deformation, making it difficult to adapt to complex and variable three-dimensional curved surface carriers. At the same time, it lacks the ability to expand modularly and replace locally damaged elements independently, resulting in poor array versatility and maintainability.

[0005] Another existing semi-flexible packaged millimeter-wave phased array technology integrates multi-channel antennas on a flexible substrate and is driven by a single RF chip, enabling small-amplitude bending and multi-directional beam coverage, thus meeting the lightweight integration requirements of small terminal devices. For example, patent document CN103493292B, entitled "System Integration and Millimeter-Wave Phased Array Antenna on Semi-Flexible Packaging," discloses the integration of multiple millimeter-wave antennas on a flexible substrate and simultaneous driving by a single RFIC, allowing multiple arrays to radiate in different spherical directions, thereby achieving three-dimensional beam coverage. However, this type of solution is only designed for lightweight devices with room temperature and small bending, and lacks multi-layer gradient thermal protection structures and phase change heat dissipation structures. It cannot achieve aerodynamic heating isolation, high heat flux impact buffering, and heat storage and heat dissipation regulation during continuous operation. Under high-temperature and complex operating conditions, it is prone to excessive temperature rise and electrical performance degradation, making it difficult to meet the requirements for long-term stable operation of radar in high-temperature environments such as airborne and missile-borne systems.

[0006] Furthermore, current optimization solutions for large phased array antennas are mostly focused on assembly process optimization. By using digital twin modeling to correct assembly errors and plan paths, the overall assembly accuracy and consistency of the antenna can be effectively improved. However, this type of optimization only improves the assembly process in the later stages and does not achieve integrated design of curved surface conformal installation, flexible signal interconnection, integrated thermal management and array status monitoring from the antenna body structure level. It lacks a complete multi-layer composite integrated structure and online sensing structure design, and cannot fundamentally solve the comprehensive technical problems of lightweight integration, flexible adaptation, high temperature protection and real-time monitoring of the working status of antennas under complex curved surface carriers.

[0007] In summary, current phased array antenna improvement schemes can only address single-dimensional technical problems. They generally suffer from a combination of defects, including poor conformal adaptation to complex three-dimensional curved surfaces, insufficient modular reconfiguration and maintenance performance, weak thermal protection and heat dissipation capabilities in high-temperature environments, and a lack of structural integration and status monitoring capabilities. They are unable to meet the multiple usage requirements of flexible conformal adaptation to large curvature surfaces, reliable operation at high temperatures over large areas, rapid modular assembly and replacement, and real-time status awareness of the array. Therefore, there is an urgent need to propose a new type of flexible conformal phased array antenna with an integrated composite structure to solve the many technical bottlenecks of existing technologies. Summary of the Invention

[0008] The purpose of this invention is to address the shortcomings of existing technologies by providing a surface radar based on a semi-flexible phased array antenna front-end and its fabrication method. This solves the problem that existing phased array structures cannot simultaneously meet the requirements of conformal mounting on complex curved surfaces, protection against high-temperature environments, heat dissipation during array operation, and reliability of flexible interconnections. This structure achieves integrated design of a transparent thermal protection layer, a phase-change heat dissipation layer, a semi-flexible phased array antenna front-end, a beam control circuit board, and a flange, integrating transparent thermal protection, heat insulation, phase-change heat storage and dissipation, conformal mounting on curved surfaces, and beam control. It effectively solves the problems of high assembly complexity, large overall weight, high interface contact thermal resistance, and insufficient operational reliability inherent in traditional discrete phased array structures, aiming to achieve high-performance integrated application of phased array antennas on complex carrier platforms.

[0009] To achieve the above objectives, the technical solution of the present invention includes the following:

[0010] A surface radar based on a semi-flexible phased array antenna front end includes a wave-transparent heat protection layer 1, a phase-change heat dissipation layer 2, a semi-flexible phased array antenna front end 3, a beam control circuit board 4, and a flange 5. The semi-flexible phased array antenna front end 3 is fixed to the outer surface of the phase-change heat dissipation layer 2 by dielectric bolts, and signal transmission between it and the beam control circuit board 4 is achieved through FPC flexible lines. The wave-transparent heat protection layer 1 and the phase-change heat dissipation layer 2 are respectively fixed to the flange 5 by bolts.

[0011] The phase change heat dissipation layer 2 is composed of a support substrate 21 and a phase change material 22, and the support substrate 21 is provided with a cavity for accommodating the phase change material 22, and the phase change material 22 is filled in the cavity; the cavity has a spatial layout and geometric shape so that the phase change heat dissipation layer 2 can enhance its thermal conductivity and heat storage and heat dissipation capacity while meeting the structural load-bearing performance.

[0012] The semi-flexible phased array antenna front end 3 includes multiple semi-flexible phased array antenna sub-array modules 31 and a flexible encapsulation layer 32; wherein the multiple semi-flexible phased array antenna sub-array modules 31 are arranged according to a predetermined array layout, and the multiple semi-flexible phased array antenna sub-array modules 31 are spliced ​​together by bonding and fixing them on the top and bottom of the flexible encapsulation layer 32, forming a flexible array structure that can be bent and deformed as a whole, so as to adapt to the conformal installation requirements of a predetermined three-dimensional curved surface or a curved surface with different curvatures.

[0013] The beam control circuit board 4 includes a communication interface, an FPGA main control chip, a frequency conversion module, an analog-to-digital converter chip, a digital-to-analog converter chip, and a sensor signal demodulation interface; wherein the communication interface is connected to the host computer for receiving beam control commands sent by the host computer; the beam control commands enter the beam control circuit board 4, are converted into control signals required by the semi-flexible phased array antenna front end 3, and are output.

[0014] Furthermore, this invention also proposes a method for manufacturing the aforementioned surface radar, comprising the following steps:

[0015] S1. Select composite material layer 11, aerogel insulation layer 12 and foam layer 13, and stack them in sequence from the outside to the inside, and then form an integrated wave-transparent heat protection layer 1 through a composite process;

[0016] S2. Based on the heat source distribution, heat flow path, structural bearing path and lightweight requirements of the semi-flexible phased array antenna front end 3, the internal cavity of the support substrate 21 is designed with topology optimization, and the support substrate 21 with internally connected cavity is prepared based on the topology optimization results.

[0017] S3. Fill the internal cavity of the support substrate 21 with phase change material 22 and seal the filling port so that the phase change material 22 is stably contained in the internal cavity of the support substrate 21, forming a phase change heat dissipation layer 2.

[0018] S4. Form array radiating units 313 and corresponding electrical connection structures on a flexible or rigid-flexible combined dielectric substrate, and periodically slot in the non-sensitive area between adjacent array radiating units to form a rigid area 311 and a flexible connection area 312, thereby obtaining a semi-flexible phased array antenna subarray module 31 with an island bridge rigid-flexible combined structure.

[0019] S5. Attach the fiber optic sensor 315 to the surface of the flexible connection area 312 and connect the signal output end of the fiber optic sensor to the signal interface of the beam control circuit board 4 or an external monitoring device.

[0020] S6. Arrange multiple semi-flexible phased array antenna sub-modules 31 according to a predetermined array layout, and bond and fix all the semi-flexible phased array antenna sub-modules through a flexible encapsulation layer 32 to form an integral semi-flexible phased array antenna front end 3.

[0021] S7. Fix the phase change heat dissipation layer 2 to the flange 5 with bolts, and then fix the semi-flexible phased array antenna front end 3 to the phase change heat dissipation layer 2 with dielectric bolts; then cover the phase change heat dissipation layer 2 and the semi-flexible phased array antenna front end 3 with the wave-transparent heat protection layer 1, and fix it to the flange 5 with bolts; finally, install the beam control circuit board 4 in the preset installation position of the flange 5 to complete the system assembly;

[0022] S8. Connect the semi-flexible phased array antenna front end 3 to the beam control circuit board 4 via FPC flexible lines, and then connect the communication interface of the beam control circuit board 4 to the host computer, task control system or external control equipment to establish a signal link, and finally realize the overall structure of the surface radar based on the semi-flexible phased array antenna front end.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] First, because the present invention uses a wave-transparent heat protection layer to set up a composite material layer, an aerogel heat insulation layer and a foam layer to form a gradient heat insulation structure, the external aerodynamic heating and high heat flow impact of the radar can be effectively isolated and buffered, greatly reducing the heat conduction from the high temperature environment to the inside of the antenna, thereby significantly improving the radar's environmental adaptability and long-term working stability under high temperature and complex working conditions.

[0025] Secondly, the present invention adopts a phase change heat dissipation layer structure with built-in topology optimization connecting cavity and filled with phase change material, so that the instantaneous high heat power consumption generated by the operation of the antenna and T / R components can be absorbed, stored and evenly diffused in a timely manner, realizing the uniform temperature heat dissipation control of the array surface, which can effectively solve the problems of excessive local temperature rise, thermal stress concentration and electrical performance degradation of traditional phased array antennas.

[0026] Third, because the present invention uses a multi-island bridge semi-flexible subarray module splicing combined with a flexible encapsulation layer and an FPC flexible interconnection structure, the antenna as a whole has the ability to compensate for local deformation and adapt to large curvature surfaces. It can realize conformal installation and modular disassembly and replacement of any complex three-dimensional curved surface carrier, thereby greatly improving the antenna's platform versatility, structural reconfigurability and subsequent maintainability.

[0027] Fourth, because the present invention adopts an integrated architecture in which the thermal protection layer, phase change heat dissipation layer, semi-flexible antenna front end, beam control circuit board and mounting flange are stacked from top to bottom, the multi-layer assembly gap and interface thermal resistance of the traditional separate structure are greatly reduced, the overall structure is highly compact and lightweight, and the combination of FPGA real-time array state perception and adaptive beam control effectively reduces assembly complexity, lightens the weight of the whole machine, and significantly improves the overall integration, mechanical reliability and beam control accuracy of the radar. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structural assembly of the present invention;

[0029] Figure 2 This is an exploded view of the structure of the present invention;

[0030] Figure 3 This is a schematic diagram of the structure of the wave-transparent heat protection layer in the present invention;

[0031] Figure 4 This is a schematic diagram of the phase change heat dissipation layer structure in the present invention;

[0032] Figure 5 This is a schematic diagram of the front-end structure of the semi-flexible phased array antenna in the present invention.

[0033] Figure 6 This is a front view of the flexible subarray after splicing in the structure of the present invention;

[0034] Figure 7 This is a schematic diagram of the back of the semi-flexible phased array antenna front end in the structure of this invention;

[0035] Figure 8 This is a schematic diagram of the conformal structure of the semi-flexible phased array antenna front end in the structure of this invention;

[0036] Figure 9 This is a front view of the semi-flexible phased array antenna subarray in the structure of the present invention;

[0037] Figure 10 This is a detailed cross-sectional schematic diagram of the semi-flexible phased array antenna subarray in the structure of this invention;

[0038] Figure 11 This is a schematic diagram of the overall appearance of the semi-flexible phased array antenna subarray in the structure of this invention;

[0039] Figure 12 This is a block diagram of the overall architecture of the radar structure of the present invention;

[0040] Figure 13 This is a flowchart illustrating the manufacturing process of the radar structure of this invention. Detailed Implementation

[0041] The present invention will now be further described with reference to the accompanying drawings.

[0042] Example 1: Refer to Figure 1-2 The surface radar based on the front end of a semi-flexible phased array antenna proposed in this invention includes a wave-transparent heat protection layer 1, a phase change heat dissipation layer 2, a semi-flexible phased array antenna front end 3, a beam control circuit board 4, and a flange 5; wherein the semi-flexible phased array antenna front end 3 is fixed to the outer surface of the phase change heat dissipation layer 2 by dielectric bolts, and signal transmission is realized between it and the beam control circuit board 4 through FPC flexible lines; the wave-transparent heat protection layer 1 and the phase change heat dissipation layer 2 are respectively fixed to the flange 5 by bolts;

[0043] The phase change heat dissipation layer 2 is composed of a support substrate 21 and a phase change material 22, and the support substrate 21 is provided with a cavity for accommodating the phase change material 22, and the phase change material 22 is filled in the cavity; the cavity has a spatial layout and geometric shape so that the phase change heat dissipation layer 2 can enhance its thermal conductivity and heat storage and heat dissipation capacity while meeting the structural load-bearing performance.

[0044] The semi-flexible phased array antenna front end 3 includes multiple semi-flexible phased array antenna sub-array modules 31 and a flexible encapsulation layer 32; wherein the multiple semi-flexible phased array antenna sub-array modules 31 are arranged according to a predetermined array layout, and the multiple semi-flexible phased array antenna sub-array modules 31 are spliced ​​together by bonding and fixing them on the top and bottom of the flexible encapsulation layer 32, forming a flexible array structure that can be bent and deformed as a whole, so as to adapt to the conformal installation requirements of a predetermined three-dimensional curved surface or a curved surface with different curvatures.

[0045] The beam control circuit board 4 includes a communication interface, an FPGA main control chip, a frequency conversion module, an analog-to-digital converter chip, a digital-to-analog converter chip, and a sensor signal demodulation interface; wherein the communication interface is connected to the host computer for receiving beam control commands sent by the host computer; the beam control commands enter the beam control circuit board 4, are converted into control signals required by the semi-flexible phased array antenna front end 3, and are output.

[0046] In this embodiment, the aforementioned dielectric bolt is used to reduce the impact of metal fasteners on the electromagnetic performance of the semi-flexible phased array antenna front end 3 while achieving mechanical fixation.

[0047] The aforementioned wave-transparent thermal protection layer 1 adopts a multi-layer composite structure, including a composite material layer 11, an aerogel insulation layer 12, and a foam layer 13 arranged sequentially from the outside to the inside. The three are integrated into a single structure through a composite process, forming a wave-transparent thermal protection structure with gradient thermal insulation function. The composite process involved here preferably adopts any one of co-curing, adhesive bonding, or hot-pressing. The composite material layer 11 is used to withstand the impact of external heat flow and airflow scouring; the aerogel insulation layer 12 is used to block the transfer of heat to the internal structure; and the foam layer 13 is used for further thermal insulation and plays a role in buffering and stress release.

[0048] The aforementioned support substrate 21 adopts an integrated structure, and its interior is provided with a cavity for accommodating the phase change material 22. The cavity is an interconnected cavity structure. The spatial layout and geometry of the cavity are determined based on the topology optimization results, so that the phase change heat dissipation layer 2 can improve the heat conduction path efficiency and the utilization rate of the phase change material 22 while meeting the structural load-bearing requirements.

[0049] The aforementioned semi-flexible phased array antenna subarray module 31 has a multilayer composite printed circuit board structure, including a top metal layer 3161, a rigid dielectric layer 3162, a metal ground layer 3163, an adhesive layer 3164, a flexible dielectric layer 3168, and a bottom bias layer 3169. The top metal layer 3161 forms the array radiating element 313 and the RF feed line; the rigid dielectric layer 3162 constitutes the rigid region 311 and supports the T / R assembly 314 and PIN diode devices; the metal ground layer... 3163 is positioned between two dielectric layers to achieve electromagnetic isolation; the adhesive film layer 3164 completes interlayer bonding; the bottom bias layer 3169 provides DC bias and control circuitry; the rigid region 311 contains metallized vias 3166 and mechanical vias 3165 penetrating each layer, the metallized vias 3166 are isolated from the metal ground layer 3163 via anti-soldering pads 3167 to connect the upper and lower circuits, and the mechanical vias 3165 are used for module positioning and fixation; a dielectric removal layer 3162 is opened between adjacent rigid regions 311. The slotted area 3170 forms a flexible connection area 312, constituting an island bridge-type rigid-flexible alternating structure. In this embodiment, the structure forms a flexible connection area 312 by periodically slotting in the non-sensitive area between adjacent array radiating units 313, so that adjacent rigid areas 311 can be electrically connected and relatively bent through the flexible connection area 312, concentrating the bending strain in the flexible connection area 312, while the rigid area 311 remains flat, thereby improving the mechanical reliability, electrical connection reliability, and electromagnetic performance stability of the array. The array radiating unit 313 is set in the rigid area 311, and the surface of the flexible connection area 312 is attached with an optical fiber sensor 315. The optical fiber sensor is used to monitor the strain, deformation, or temperature state of the semi-flexible phased array antenna subarray module 31 during the bending deformation process in real time, and transmits the monitoring signal to the beam control circuit board 4 or external monitoring equipment to realize real-time perception of the working state and conformal deformation state of the semi-flexible phased array antenna front end 3.

[0050] After receiving the beam control command sent by the host computer, the beam control circuit board 4 is parsed by the FPGA main control chip and generates beam control signals corresponding to each semi-flexible phased array antenna sub-array module 31 according to the beam control command. The beam control signals are output to each T / R component 314 through the FPC flexible line to control the transmit and receive status, amplitude weighting and phase weighting of each T / R component 314.

[0051] Example 2: The overall structure of the surface radar proposed in this example is the same as in Example 1, and will now be referred to... Figure 1-12 The invention provides specific examples to further describe the structural composition of the radar of the present invention:

[0052] The radar comprises a wave-transparent thermal protection layer 1, a phase-change heat dissipation layer 2, a semi-flexible phased array antenna front end 3, a beam control circuit board 4, and a flange 5. The wave-transparent thermal protection layer 1 is located on the outer side of the structure and is used to withstand external heat flow impact, aerodynamic heating, and environmental loads. The semi-flexible phased array antenna front end 3 is positioned between the wave-transparent thermal protection layer 1 and the phase-change heat dissipation layer 2, and is used to achieve beam scanning, beam pointing adjustment, and electromagnetic signal transmission and reception in a conformal curved surface state. The beam control circuit board 4 is used to receive external control commands and send control signals to the semi-flexible phased array antenna front end 3. The flange 5 is used to secure the overall structure to the external carrier platform.

[0053] Reference Figure 1-2 In this embodiment, the wave-transparent thermal protection layer 1 and the phase-change heat dissipation layer 2 are stacked along the thickness direction and fixed to the flange 5 by bolts. A thermally conductive interface material can be further provided at the assembly interface between the wave-transparent thermal protection layer 1 and the phase-change heat dissipation layer 2 to fill the tiny gaps at the contact interface, reduce the interface contact thermal resistance, and improve the heat transfer efficiency between the wave-transparent thermal protection layer 1 and the phase-change heat dissipation layer 2. The semi-flexible phased array antenna front end 3 is fixed to the phase-change heat dissipation layer 2 by dielectric bolts. The dielectric bolts are used to achieve mechanical fixation while reducing the influence of metal fasteners on the electromagnetic performance of the semi-flexible phased array antenna front end 3.

[0054] Reference Figure 3 In this embodiment, the wave-transparent thermal protection layer 1 adopts a multi-layer composite structure, including a composite material layer 11, an aerogel insulation layer 12, and a foam layer 13 arranged sequentially from the outside to the inside. The composite material layer 11 is located on the outer side of the wave-transparent thermal protection layer 1, serving to withstand external heat flow impact, airflow erosion, and environmental loads. The aerogel insulation layer 12 is disposed between the composite material layer 11 and the foam layer 13, serving to reduce heat transfer to the internal structure. The foam layer 13 is located on the inner side of the wave-transparent thermal protection layer 1, serving to fix the aerogel insulation layer 12 and further providing insulation, buffering, and stress relief. The composite material layer 11, the aerogel insulation layer 12, and the foam layer 13 are integrated into a single structure through co-curing, adhesive bonding, hot-pressing, or other composite processes, collectively constituting the wave-transparent thermal protection layer 1 with gradient thermal insulation function.

[0055] Reference Figure 4In this embodiment, the phase change heat dissipation layer 2 includes a supporting substrate 21 and a phase change material 22. The supporting substrate 21 is an integral structure with a cavity inside for accommodating the phase change material 22. The phase change material 22 fills the cavity and contacts the inner wall of the cavity of the supporting substrate 21. The cavity is preferably an interconnected cavity structure, and its spatial layout and geometry are determined based on topology optimization results, so that the supporting substrate 21 forms a spatial structure that serves both as a heat conduction channel and a load-bearing support. In this embodiment, the topology optimization design of the cavity inside the supporting substrate 21 is based on the heat source distribution, heat flow path, structural load-bearing path, and lightweight requirements of the semi-flexible phased array antenna front end 3. Through this topology optimization cavity structure, the phase change heat dissipation layer 2 can improve the efficiency of the heat conduction path and the effective utilization rate of the phase change material 22 while meeting the structural load-bearing requirements. When the semi-flexible phased array antenna front end 3 generates heat during operation, the heat is transferred to the phase change material 22 through the supporting substrate 21. The phase change material 22 absorbs and stores the heat through the phase change process, thereby reducing the temperature rise of the semi-flexible phased array antenna front end 3 and improving the thermal stability of the structure under high heat environment and continuous working conditions.

[0056] Reference Figure 5 The semi-flexible phased array antenna front-end 3 in this embodiment includes multiple semi-flexible phased array antenna sub-array modules 31 and a flexible encapsulation layer 32. The multiple semi-flexible phased array antenna sub-array modules 31 are arranged according to a predetermined array layout and spliced ​​together by the flexible encapsulation layer 32 to form an integral semi-flexible phased array antenna front-end 3.

[0057] Reference Figure 5 In this embodiment, the flexible encapsulation layer 32 is a flexible thin film layer attached to the surface of multiple semi-flexible phased array antenna sub-modules 31. The flexible thin film layer is bonded and fixed to adjacent semi-flexible phased array antenna sub-modules 31, allowing the multiple semi-flexible phased array antenna sub-modules 31 to connect and form an integral semi-flexible phased array antenna front end 3, and enabling it to bend and deform together with the semi-flexible phased array antenna sub-modules 31. The flexible encapsulation layer 32 can be made of polyimide film, liquid crystal polymer film, polyester film, silicone rubber film, or other flexible insulating film materials. By setting the flexible encapsulation layer 32, the overall continuity and structural stability between the multiple semi-flexible phased array antenna sub-modules 31 can be improved.

[0058] Reference Figure 5-11In this embodiment, the semi-flexible phased array antenna subarray module 31 adopts an island-bridge rigid-flexible structure, including a rigid region 311, a flexible connection region 312, radiating elements 313, and a T / R assembly 314. The semi-flexible phased array antenna subarray module 31 has periodic slots in the non-sensitive areas between adjacent array radiating elements 313 to form the flexible connection region 312. The non-sensitive area refers to the area that has little impact on the main radiation performance, feeding performance, or inter-element electromagnetic coupling of the array radiating elements 313. The T / R assembly is located in the rigid region on the back side of the semi-flexible phased array antenna subarray module.

[0059] Reference Figure 5-11 In this embodiment, the array radiating element 313 is disposed within the rigid region 311. The rigid region 311 serves to support the array radiating element 313 and related circuit structures, ensuring that the array radiating element 313 remains relatively flat even when the semi-flexible phased array antenna sub-module 31 undergoes bending deformation. Adjacent rigid regions 311 are electrically connected and subjected to relative bending deformation via flexible connecting regions 312. When the semi-flexible phased array antenna sub-module 311 undergoes bending deformation, the deformation is mainly concentrated in the flexible connecting regions 312, thereby reducing the local deformation of the rigid region 311 where the array radiating element 313 is located. This helps maintain the positional accuracy and electromagnetic performance stability of the array radiating element 313.

[0060] Reference Figure 6 In this embodiment, an optical fiber sensor 315 is attached to the surface of the flexible connection region 312. The optical fiber sensor 315 can be a strain sensor, temperature sensor, deformation sensor, fiber Bragg grating sensor, or a combination thereof, used to monitor the strain, deformation, or temperature state of the semi-flexible phased array antenna subarray module 31 during bending deformation in real time. The monitoring signal collected by the optical fiber sensor 315 can be transmitted to the beam control circuit board 4 or external monitoring equipment to realize real-time perception of the working state and conformal deformation state of the semi-flexible phased array antenna front end 3.

[0061] Reference Figure 10In this embodiment, the semi-flexible phased array antenna subarray module 31 is fabricated using a multilayer printed circuit board process, including a top metal layer 3161, a first dielectric layer 3162, a metal ground layer 3163, an adhesive layer 3164, mechanical vias 3165, metallized vias 3166, anti-pads 3167, a second dielectric layer 3168, and a bottom bias layer 3169. First, the first dielectric layer 3162, the metal ground layer 3163, the adhesive layer 3164, and the second dielectric layer 3168 are sequentially stacked and laminated to form a composite dielectric substrate. Then, a top metal layer 3161 is formed on the top layer of the composite dielectric substrate, and a bottom bias layer 3169 is formed on the bottom layer. Array radiating elements 313, feed lines, DC bias lines, control lines, and device pads are then fabricated. Finally, metallized vias 3166 and mechanical vias 3165 are fabricated within the rigid region 311. The metallized via 3166 is used to achieve electrical connection between the top metal layer 3161 and the bottom bias layer 3169; the mechanical via 3165 is used to achieve installation, positioning, and mechanical fixation of the semi-flexible phased array antenna subarray module 31. Anti-soldering pads 3167 are provided at the locations where the metallized via 3166 passes through the metal ground layer 3163 to maintain electrical isolation between the metallized via 3166 and the metal ground layer 3163, while ensuring that control signals and bias signals can be transmitted from the bottom bias layer 3169 to the top device. Subsequently, slotting is performed in the non-sensitive area between adjacent array radiating elements 313 to remove dielectric layer 3162, leaving the metal ground layer 3163, adhesive layer 3164, dielectric layer 3168, and bottom bias layer 3169 between adjacent rigid areas 311, thereby forming a flexible connection area 312. The flexible connection region 312 maintains the electrical continuity between adjacent rigid regions 311 and also serves as a flexible hinge structure when the semi-flexible phased array antenna sub-module 311 bends. Finally, the T / R component 314, PIN diodes, and other electronic devices are mounted on the corresponding device pads within the rigid region 311 using surface mount technology, completing the electrical connection between the bottom bias circuit and the top device, thus forming the semi-flexible phased array antenna sub-module 31. In this embodiment, since the rigid region 311 retains the complete thickness of the composite dielectric substrate, while the flexible connection region 312 only retains the structural layer for electrical connection and flexible support, when the semi-flexible phased array antenna sub-module 311 is mounted on a curved surface or undergoes bending deformation, the bending strain is mainly concentrated in the flexible connection region 312. The rigid region 311 where the array radiating unit 313, T / R component 314, and related solder joints are located remains basically flat, thereby improving the device mounting reliability, array structure stability, and electromagnetic performance stability.

[0062] Reference Figure 12In this embodiment, when the radar is in receiving mode, after the semi-flexible phased array antenna front-end 3 receives the spatial radio frequency signal, the T / R components 314 corresponding to each semi-flexible phased array antenna subarray module 31 perform amplitude limiting protection, low-noise amplification, amplitude weighting, and phase weighting processing on the radio frequency signal. The multiple radio frequency signals are combined and then input to the frequency conversion module. The frequency conversion module performs down-conversion processing on the combined radio frequency signal to form an intermediate frequency signal. The intermediate frequency signal is converted into a digital signal by an analog-to-digital converter chip and then sent to the FPGA main control chip for digital signal processing. In transmitting mode, the digital transmission signal output by the FPGA main control chip is converted into an analog signal by a digital-to-analog converter chip. The analog signal is up-converted to the radio frequency band by the frequency conversion module and then input to the T / R components 314 corresponding to each semi-flexible phased array antenna subarray module 31. The T / R component 314 performs phase shifting, amplitude weighting, and power amplification on the radio frequency signal, and radiates it into space through the array radiation unit 313, so that the radio frequency signals emitted by multiple semi-flexible phased array antenna sub-modules 31 are combined into a target beam in space. Simultaneously, fiber optic sensors integrated into the front-end 3 of the semi-flexible phased array antenna are used to collect real-time data on array surface strain, temperature, or deformation. The collected sensor signals are input to the FPGA main control chip via the sensor signal demodulation interface. The FPGA main control chip outputs or corrects the beam control signal of the front-end 3 of the semi-flexible phased array antenna according to the array surface state data, beam control commands, and preset control strategies, thereby achieving the integration of electromagnetic signal transmission and reception, array surface state sensing, and beam amplitude and phase modulation.

[0063] Example 3: Refer to Figure 13 This embodiment provides a method for fabricating a surface radar based on the front end of a semi-flexible phased array antenna, including the following steps:

[0064] Step S1. Prepare the wave-transparent heat protection layer 1: Select the composite material layer 11, the aerogel heat insulation layer 12 and the foam layer 13, and stack them in sequence from the outside to the inside. Then, form an integrated wave-transparent heat protection layer 1 through co-curing, adhesive bonding, hot pressing or other composite processes. In this embodiment, it is preferred to form the integrated wave-transparent heat protection layer 1 through co-curing.

[0065] Step S2. Fabrication of phase change heat dissipation layer 2: Based on the heat source distribution, heat flow path, structural bearing path and lightweight requirements of the semi-flexible phased array antenna front end 3, the internal cavity of the support substrate 21 is designed with topology optimization, and the support substrate 21 with internally connected cavity is fabricated based on the topology optimization results.

[0066] Step S3. Filling phase change material 22: Fill the internal cavity of the support substrate 21 with phase change material 22 and seal the filling port so that the phase change material 22 is stably contained in the internal cavity of the support substrate 21, forming a phase change heat dissipation layer 2.

[0067] Step S4. Fabrication of semi-flexible phased array antenna sub-module 31: Array radiation unit 313 and corresponding electrical connection structure are formed on a flexible or rigid-flexible combined dielectric substrate, and periodic slots are made in the non-sensitive area between adjacent array radiation units to form a rigid area 311 and a flexible connection area 312, thereby obtaining a semi-flexible phased array antenna sub-module 31 with an island bridge rigid-flexible combined structure.

[0068] Step S5. Deploy fiber optic sensor 315: Attach fiber optic sensor 315 to the surface of flexible connection area 312, and connect the signal lead-out end of fiber optic sensor to the signal interface of beam control circuit board 4 or external monitoring equipment.

[0069] Step S6. Splicing the semi-flexible phased array antenna front end 3: Arrange multiple semi-flexible phased array antenna sub-array modules 31 according to a predetermined array layout, and bond and fix all the semi-flexible phased array antenna sub-array modules through the flexible encapsulation layer 32 to form an integral semi-flexible phased array antenna front end 3.

[0070] Step S7. System Assembly: Fix the phase change heat dissipation layer 2 to the flange 5 with bolts, and then fix the semi-flexible phased array antenna front end 3 to the phase change heat dissipation layer 2 with dielectric bolts; then cover the phase change heat dissipation layer 2 and the semi-flexible phased array antenna front end 3 with the wave-transparent heat protection layer 1, and fix it to the flange 5 with bolts; finally, install the beam control circuit board 4 in the preset installation position of the flange 5 to complete the system assembly;

[0071] Step S8. Establish signal link: Connect the semi-flexible phased array antenna front end 3 to the beam control circuit board 4 through the FPC flexible line, and then connect the communication interface of the beam control circuit board 4 to the host computer, task control system or external control equipment to establish a signal link, and finally realize the overall structure of surface radar based on the semi-flexible phased array antenna front end.

[0072] This invention integrates a transparent thermal protection layer, a phase change heat dissipation layer, a flexible phased array, a beam control circuit board, and a flange into a single integrated structure. This achieves thermal protection, insulation, phase change heat storage and dissipation, conformal mounting on curved surfaces, and beam control. Mechanical and signal connections are achieved throughout using dielectric bolts and FPC flexible wiring, effectively improving the reliability and assembly consistency of complex curved phased array antennas in high-temperature environments. The assembly and use of this invention are implemented on a complex three-dimensional curved surface carrier, characterized by large curvature variations, limited installation space, and high requirements for electromagnetic performance and thermal management. Compared to existing inventions that can only use rigid planar arrays or simple fixed conformal structures, this invention greatly expands the application range of phased array antennas on various complex platforms. The structure of this invention, by using a stacked installation of the transparent thermal protection layer and the phase change heat dissipation layer, and fixing the front end of the semi-flexible phased array antenna to the phase change heat dissipation layer with dielectric bolts, enables flexible conformal mounting and efficient thermal management of complex curved surfaces. This solves the problems of poor adaptability, high thermal resistance, and complex assembly in existing technologies, and improves the flexibility and reliability of the structure compared to fixed fixtures or separate heat dissipation methods. Furthermore, by integrating thermal protection, phase change heat dissipation, island-bridge flexible array and status monitoring, this invention can achieve integrated functions of curved surface conformal, thermal management and beam control. Compared with the prior art, this invention not only includes the basic structure and manufacturing process, but also real-time status perception and closed-loop thermal management, and belongs to a complete and integrated surface radar at the front end of a semi-flexible phased array antenna.

[0073] The parts of this invention not described in detail are common knowledge to those skilled in the art.

[0074] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Obviously, those skilled in the art, after understanding the content and principle of the present invention, may make various modifications and changes in form and detail without departing from the principle and structure of the present invention. However, these modifications and changes based on the concept of the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A surface radar based on the front end of a semi-flexible phased array antenna, characterized in that, include: The structure consists of a wave-transparent heat protection layer (1), a phase-change heat dissipation layer (2), a semi-flexible phased array antenna front end (3), a beam control circuit board (4), and a flange (5); wherein the semi-flexible phased array antenna front end (3) is fixed to the outer surface of the phase-change heat dissipation layer (2) by dielectric bolts, and signal transmission is achieved between it and the beam control circuit board (4) through FPC flexible lines; the wave-transparent heat protection layer (1) and the phase-change heat dissipation layer (2) are respectively fixed to the flange (5) by bolts; The phase change heat dissipation layer (2) is composed of a support substrate (21) and a phase change material (22), and the support substrate (21) is provided with a cavity for accommodating the phase change material (22), and the phase change material (22) is filled in the cavity; the cavity has a spatial layout and geometric shape so that the phase change heat dissipation layer (2) can enhance its thermal conductivity and heat storage and heat dissipation capacity while meeting the structural load-bearing performance. The semi-flexible phased array antenna front end (3) includes multiple semi-flexible phased array antenna sub-array modules (31) and a flexible encapsulation layer (32); wherein the multiple semi-flexible phased array antenna sub-array modules (31) are arranged according to a predetermined array layout, and the multiple semi-flexible phased array antenna sub-array modules (31) are spliced ​​together by the flexible encapsulation layer (32) on its upper and lower surfaces to form a flexible array structure that can be bent and deformed as a whole, so as to adapt to the conformal installation requirements of a predetermined three-dimensional curved surface or a curved surface with different curvatures; The beam control circuit board (4) includes a communication interface, an FPGA main control chip, a frequency conversion module, an analog-to-digital converter chip, a digital-to-analog converter chip, and a sensor signal demodulation interface; wherein the communication interface is connected to the host computer for receiving beam control commands sent by the host computer; the beam control commands enter the beam control circuit board (4), are converted into control signals required by the semi-flexible phased array antenna front end (3), and output.

2. The radar according to claim 1, characterized in that: The dielectric bolt is used to reduce the impact of metal fasteners on the electromagnetic performance of the semi-flexible phased array antenna front end (3) while achieving mechanical fixation.

3. The area radar according to claim 1, characterized in that: The wave-transparent thermal protection layer (1) adopts a multi-layer composite structure, including a composite material layer (11), an aerogel insulation layer (12), and a foam layer (13) arranged sequentially from the outside to the inside. The three are integrated into a single structure through a composite process, which together constitutes a wave-transparent thermal protection structure with gradient thermal insulation function. The composite material layer (11) is used to withstand the impact of external heat flow and the scouring of airflow; the aerogel insulation layer (12) is used to block the transfer of heat to the internal structure; and the foam layer (13) is used to further insulate the heat and play a role in buffering and stress release.

4. The radar according to claim 3, characterized in that: The composite process includes co-curing, adhesive bonding, and hot-pressing.

5. The radar according to claim 1, characterized in that: The supporting substrate (21) adopts an integrated structure, and its interior is provided with a cavity for accommodating the phase change material (22). The cavity is an interconnected cavity structure. The spatial layout and geometry of the cavity are determined based on the topology optimization results so that the phase change heat dissipation layer (2) can improve the heat conduction path efficiency and the utilization rate of the phase change material (22) while meeting the structural load requirements.

6. The surface radar according to claim 1, characterized in that: The semi-flexible phased array antenna subarray module (31) is a multi-layer composite printed circuit board structure, including a top metal layer (3161), a rigid dielectric layer (3162), a metal ground layer (3163), an adhesive film layer (3164), a flexible dielectric layer (3168), and a bottom bias layer (3169). The top metal layer (3161) forms the array radiating unit (313) and the radio frequency feed line. The rigid dielectric layer (3162) forms a rigid region (311) and carries the T / R component (314) and PIN diode device; the metal ground layer (3163) is located between the two dielectric layers to achieve electromagnetic isolation; the adhesive film layer (3164) completes the interlayer lamination; the bottom bias layer (3169) is provided with DC bias and control lines; the rigid region (311) is provided with metallized vias (3166) and mechanical vias (3165) that penetrate each layer. The metallized vias (3166) are isolated from the metal ground layer (3163) through anti-soldering pads (3167) to connect the upper and lower circuits, and the mechanical vias (3165) are used for module positioning and fixing; a slotted area (3170) for removing the dielectric layer (3162) is opened between adjacent rigid regions (311) to form a flexible connection area (312), forming an island bridge-type rigid-flexible alternating structure.

7. The surface radar according to claim 6, characterized in that: The island-bridge type rigid-flexible alternating structure is formed by periodically slotting non-sensitive areas between adjacent array radiation units (313) to create a flexible connection area (312), so that adjacent rigid areas (311) can be electrically connected and relatively bent through the flexible connection area (312), and the bending strain is concentrated in the flexible connection area (312), while the rigid area (311) remains flat, thereby improving the mechanical reliability, electrical connection reliability and electromagnetic performance stability of the array. The array radiation unit (313) is set in the rigid area (311), and the fiber optic sensor (315) is attached to the surface of the flexible connection area (312).

8. The radar according to claim 7, characterized in that: The fiber optic sensor (315) is used to monitor the strain, deformation or temperature state of the semi-flexible phased array antenna subarray module (31) during the bending deformation process in real time, and transmit the monitoring signal to the beam control circuit board (4) or external monitoring equipment to realize the real-time perception of the working state and conformal deformation state of the semi-flexible phased array antenna front end (3).

9. The radar according to claim 1, characterized in that: After receiving the beam control command sent by the host computer, the beam control circuit board (4) parses the beam control command by the FPGA main control chip and generates beam control signals corresponding to each semi-flexible phased array antenna sub-array module (31) according to the beam control command. The beam control signals are output to each T / R component (314) through the FPC flexible line to control the transmit and receive status, amplitude weighting and phase weighting of each T / R component (314).

10. A method for manufacturing any one of the surface radars according to claims 1-9, characterized in that, Includes the following steps: S1. Select the composite material layer (11), the aerogel insulation layer (12) and the foam layer (13), and stack them in sequence from the outside to the inside. Then, form an integrated wave-transparent heat protection layer (1) through a composite process. S2. Based on the heat source distribution, heat flow path, structural bearing path and lightweight requirements of the semi-flexible phased array antenna front end (3), the internal cavity of the support substrate (21) is designed with topology optimization, and the support substrate (21) with internal connected cavity is prepared according to the topology optimization results. S3. Fill the internal cavity of the support substrate (21) with phase change material (22) and seal the filling port so that the phase change material (22) is stably contained in the internal cavity of the support substrate (21) to form a phase change heat dissipation layer (2). S4. Form array radiating units (313) and corresponding electrical connection structures on a flexible or rigid-flexible combined dielectric substrate, and periodically slot in the non-sensitive area between adjacent array radiating units to form a rigid area (311) and a flexible connection area (312), thereby processing a semi-flexible phased array antenna sub-array module (31) with an island bridge rigid-flexible combined structure. S5. Attach an optical fiber sensor (315) to the surface of the flexible connection area (312) and connect the signal output end of the optical fiber sensor to the beam control circuit board (4) or the signal interface of an external monitoring device. S6. Arrange multiple semi-flexible phased array antenna sub-modules (31) according to a predetermined array layout, and bond and fix all the semi-flexible phased array antenna sub-modules through a flexible encapsulation layer (32) to form an integral semi-flexible phased array antenna front end (3). S7. Fix the phase change heat dissipation layer (2) to the flange (5) with bolts, and then fix the semi-flexible phased array antenna front end (3) to the phase change heat dissipation layer (2) with dielectric bolts; then cover the phase change heat dissipation layer (2) and the semi-flexible phased array antenna front end (3) with the wave-transparent heat protection layer (1), and fix it to the flange (5) with bolts; finally, install the beam control circuit board (4) at the preset installation position of the flange (5) to complete the system assembly; S8. Connect the semi-flexible phased array antenna front end (3) to the beam control circuit board (4) through the FPC flexible line, and then connect the communication interface of the beam control circuit board (4) to the host computer, task control system or external control equipment to establish a signal link, and finally realize the overall structure of the surface radar based on the semi-flexible phased array antenna front end.

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