Built-in conformal fiber electric field sensor array test system and method

Abstract

The application belongs to the technical field of high-power microwave effect test in laboratory, and relates to a built-in conformal optical fiber electric field sensor array test system and method. The method comprises the following steps: step S1, a step of implementing previous preparation; step S2, a step of quick assembly and disassembly; step S3, a step of real-time measurement and closed loop; step S4, a step of result confirmation and log uploading; and step S5, a step of preparation for the next round of experiment. The technical scheme is mainly used for distributed measurement of internal electric field of a test body fixed or supported by a sliding rail in a shielding cabin, a tight field or a GTEM chamber and the like. The system is composed of a conformal optical fiber electric field sensor array, an optical fiber link unit, an optoelectronic integrated module, a self-calibration unit and energy and an interface, can be assembled and disassembled within 5 minutes, can be repeatedly used more than 100 times, significantly reduces the operation cost of a laboratory, and provides a core test means for high-precision, high-efficiency and low-cost HPM effect test of anti-missile weapons.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of high-power microwave (HPM) effect test in the laboratory, and particularly relates to an in-built conformal optical fiber electric field sensor array test system and method. BACKGROUND

[0002] In the existing laboratory high-power microwave (HPM) effect test, electric field measurement mainly relies on external metal probes or cavity field monitors, which is difficult to truly reflect the internal electromagnetic coupling condition of the test body. The traditional metal coaxial probe is prone to tip discharge in a high field strength (greater than 50 kV / m) environment, resulting in data distortion and even premature termination of the test. The traditional optical fiber sensing scheme is mostly point type and rigidly packaged, which requires additional support, occupies cabin space, and destroys the original configuration of the measured object, affecting the authenticity of the test. In addition, the existing system generally lacks automatic calibration and temperature drift compensation capability, and the long-term measurement uncertainty is more than 10%, which is difficult to meet the core requirements of long-term accurate, stable and reliable measurement data. Although the laboratory environment does not require the sensor to have high overload capacity, it puts forward higher demands on installation efficiency, reusability and compatibility with existing tight field turntables and other equipment. This is the deficiency of the prior art.

[0003] Therefore, it is necessary to provide an in-built conformal optical fiber electric field sensor array test system and method to solve the above-mentioned defects in the prior art. SUMMARY

[0004] The purpose of the present application is to provide an in-built conformal optical fiber electric field sensor array test system and method to solve the above-mentioned technical problems in view of the defects of the prior art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme:

[0006] An in-built conformal optical fiber electric field sensor array test method, comprising the following steps:

[0007] Step S1, a step of pre-preparation, in which:

[0008] The test body is positioned, the conformal optical fiber electric field sensor array is self-checked, and the time reference of the edge node and the conformal optical fiber electric field sensor is aligned.

[0009] Step S2, a quick mounting and dismounting step, in which:

[0010] The conformal optical fiber electric field sensor array is attached on the fixed test body, the plastic optical fiber is penetrated, and the optical fiber jumper is connected to the optoelectronic integrated case outside the shielding cabin; remote one-key self-calibration is performed, and the data channel is checked.

[0011] Step S3, the step of real-time measurement and closed loop, in which:

[0012] After the start of the test, enter the real-time measurement state, collect the electric field, process the data through the edge GPU node, and finally visualize in real time through WebGL.

[0013] Step S4, the step of result confirmation and log upload, in which:

[0014] After the end of a single test, compare and automatically verify the measured electric field distribution with the results of the pre-performed CST simulation (CST Studio Suite professional three-dimensional electromagnetic field simulation software);

[0015] Automatically generate a CSV file (containing initial frequency, measured electric field, error, time consumption, timestamp, etc.) and upload it to the Web server, and use hash chaining technology to store the evidence and prevent data tampering.

[0016] Step S5, the step of preparation for the next round of experiments, in which:

[0017] Reset the initial frequency parameter, measured electric field parameter, error parameter, time consumption parameter, timestamp parameter, and other parameters for the next step; automatically complete sensor zero calibration, archive the log of the previous round of experiments, and start the new round of experiment preparation process.

[0018] As a preferred embodiment, the step S1 specifically includes:

[0019] Position the test body, fix the multi-mode test body horizontally on the compact field support, ensure that it has sufficient anti-vibration capability (more than 30g), and ensure that there is no metal cable passing through the shield cabin wall;

[0020] Perform self-checking of the conformal optical fiber electric field sensor array, collect electric field amplitudes with a spatial density of not less than 20 points per meter, and obtain the detection data; the detection data is fed back to the edge GPU node through the link of plastic optical fiber combined with CAN-FD, and there is no metal throughout the process;

[0021] Align the time reference of the edge GPU node and all conformal optical fiber electric field sensors to within 1 ns through the White-Rabbit clock synchronization protocol, and ensure strict synchronization of multi-channel data collection.

[0022] As a preferred embodiment, the step S2 specifically includes:

[0023] One-time paste the conformal optical fiber electric field sensor array to the inner wall curve of the test body through thermal conductive glue;

[0024] Lay and pass through a single plastic optical fiber (outer diameter not more than 3 mm), tighten the through-cabin sealing sleeve, ensure the integrity of the shielding, and there is no metal component throughout the process;

[0025] Outside the shielded cabin, the plastic optical fiber jumper is connected to the optoelectronic integrated case using an SMA-905 plastic optical fiber connector;

[0026] Remote triggering of one-key self-calibration through a Web interface automatically completes the calibration of the built-in conformal optical fiber electric field sensor array;

[0027] Automatic checking of the connectivity and signal quality of all data channels;

[0028] Calibration and automatic checking are error-free, and the experiment is ready for immediate start of the HPM irradiation test (the disassembly process is performed in the reverse order, with the same efficiency).

[0029] The calibration of the conformal optical fiber electric field sensor array through the remote triggering of one-key self-calibration through a Web interface specifically includes:

[0030] After starting the self-calibration, the miniature patch TEM cell integrated in the inner wall of the test body generates a standard (1 GHz, 50 V / m) square wave calibration field. The responses of all conformal optical fiber electric field sensors are collected, and the calibration coefficients of each channel, including the gain coefficient and the offset coefficient, are calculated and directly written into the internal RAM of the FPGA phase-locked demodulation circuit for real-time correction during the test process;

[0031] The FBG temperature reference piece performs 1 kHz synchronous sampling, and the temperature change ΔT is calculated from the temperature sensitivity coefficient according to the reflection wavelength change ΔλB of the FBG temperature reference piece; when the temperature change ΔT is less than 5℃, the electric field measurement value is automatically temperature-compensated to realize temperature-electric field decoupling; according to the LiNbO3 temperature sensitivity coefficient pre-stored in the FPGA phase-locked demodulation circuit , the original electric field change measured by the LiNbO3 thin film electro-optic modulation microstrip is corrected in real time to obtain the decoupled electric field value , and the correction formula is: .

[0032] As a preferred, the step S3 specifically includes:

[0033] Electric field acquisition is performed, the LiNbO3 thin film electro-optic modulation microstrip senses the electric field change, and the signal is transmitted through a single PM1550 polarization maintaining optical fiber.

[0034] Edge GPU processing is performed, the edge GPU node receives data, performs parallel calculation, and performs voxelization and VolumeRayCaster volume rendering through WebGL shared video memory (the entire processing and rendering delay is less than 100 milliseconds), and the entire process is guaranteed by a White-Rabbit clock (the timestamp accuracy is better than 1 ns).

[0035] It performs real-time visualization using WebGL, processes the generated electric field distribution data, performs volume rendering using WebGL 2.0 technology, and outputs the data to a web interface, supporting real-time observation through multiple interactive modes such as mouse, touch screen, and VR headset.

[0036] Furthermore, the present invention also provides a test system for a built-in conformal fiber electric field sensor array, comprising:

[0037] Completely integrated within the test specimen, with no metal feed lines protruding from the test piece, it can be installed or disassembled within 5 minutes and can be reused at least 100 times. Specifically, it includes: a conformal fiber electric field sensor array, a fiber optic link module, an optoelectronic integration module, a self-calibration module, an energy module, and an interface module.

[0038] The fiber optic link module uses a single PM1550 polarization-maintaining fiber to connect all conformal fiber electric field sensors in series, forming a conformal fiber electric field sensor array without fusion splices. The tail end of the PM1550 polarization-maintaining fiber is connected to the fiber optic patch cord of the plastic fiber via an SMA-905 plastic fiber connector. The fiber optic patch cord of the plastic fiber passes through the shielded chamber and connects to the optoelectronic integrated chassis. The optoelectronic integrated module is integrated into the optoelectronic integrated chassis. The self-calibration module uses a miniature patch TEM chamber, which is bonded to the curved surface of the inner wall of the test chamber with peelable thermally conductive adhesive. The energy module provides power to the optoelectronic integrated module. The interface module uses a chamber wall sealing structure to ensure the electromagnetic shielding integrity and airtightness at the point where the plastic fiber passes through the chamber.

[0039] Preferably, the conformal fiber electric field sensor array includes:

[0040] Multiple LiNbO3 thin-film electro-optic modulation microstrips are attached to the curved surface of the inner wall of the test chamber using a peelable thermally conductive adhesive, conforming to the inner wall. The LiNbO3 thin-film electro-optic modulation microstrips have dimensions of 0.3 mm × 5 mm × 15 μm, a sensitivity exceeding 0.4 mV / (V / m) under laboratory conditions, a measurement range exceeding 100 kV / m, a working bandwidth of DC-18 GHz, and a rise time of less than 1 ns. The LiNbO3 thin-film electro-optic modulation microstrips are integrally formed using ion slicing and dry etching processes, with a film thickness of less than 600 nanometers, enabling conformal mounting. The conformal fiber electric field sensor array has a total length of 50 mm, employing a spiral measurement chain layout to cover three typical areas: the first, middle, and last compartments, with a measurement point density greater than 20 points / meter.

[0041] The LiNbO3 thin-film electro-optic modulated microstrip and conformal fiber electric field sensor array meet the following specifications: after undergoing no less than 120 high-power microwave irradiation experiments with a peak field strength of no less than 60 kV / m, the LiNbO3 thin-film electro-optic modulated microstrip shows no cracks; the increase in optical insertion loss is less than 0.2 dB; and the drift of the sensor calibration coefficient is less than 1.5%.

[0042] Preferably, the fiber optic link module includes:

[0043] An FBG temperature reference sheet (fiber Bragg grating temperature reference sheet) with a thickness of less than 50 μm is attached to the same position as the LiNbO3 thin film electro-optic modulation microstrip. Its temperature sensitivity is about 10 pm / ℃, and it is used for automatic temperature decoupling correction when ΔT < 5 ℃. The core function of the FBG temperature reference sheet is to provide a temperature reference for the conformal fiber electric field sensor in real time and purely optically without destroying the electric field measurement, thereby decoupling the interference of temperature on the electric field reading.

[0044] The PM1550 polarization-maintaining fiber optic cable's tail end passes through the laboratory floor grounding shielding mesh via an SMA-905 plastic fiber optic connector, without compromising the integrity of the shielding chamber.

[0045] Preferably, the optoelectronic integrated module includes:

[0046] DFB laser, balanced detector, FPGA phase-locked demodulation circuit; DFB laser, balanced detector, FPGA phase-locked demodulation circuit are electrically connected in sequence;

[0047] The DFB laser (a single-mode semiconductor laser with a built-in distributed feedback grating) serves as the core light source component of the optoelectronic integrated module, generating an optical signal with a wavelength of 1550 nm and a linewidth of less than 1 MHz. The optical signal generated by the DFB laser is transmitted via plastic optical fiber to a LiNbO3 thin-film electro-optic modulation microstrip located in a shielded chamber for electro-optic modulation, generating a weak optical signal. The balanced detector has a common-mode rejection ratio greater than 40 dB and is responsible for converting the weak optical signal generated by the LiNbO3 thin-film electro-optic modulation microstrip into a voltage signal with high fidelity and outputting it for FPGA phase-locked demodulation. The FPGA phase-locked demodulation circuit supports a sampling rate of 1 kHz and a processing delay of less than 50 ms during the self-calibration stage. It is responsible for receiving the voltage signal output by the balanced detector and realizing the functions of writing calibration coefficients, temperature-electric field decoupling, and fault channel marking.

[0048] The optoelectronic integrated module has an embedded web server that connects to the laboratory data acquisition system via a LAN interface, enabling remote one-click start-up, calibration, fault marking, and data download.

[0049] Preferably, the self-calibration module includes:

[0050] The miniature patch TEM cell, with a size not exceeding 40 mm × 20 mm × 2 mm, is bonded to the inner curved surface of the test chamber by a peelable thermally conductive adhesive, and is conformally positioned with the conformal fiber electric field sensor.

[0051] The miniature patch TEM cell generates a 1 GHz / 50 V / m square wave calibration field for automatic calibration before the experiment. The calibration time for a single channel is less than 50 ms. The calibration coefficients obtained by automatic calibration will be stored in the FPGA phase-locked demodulation circuit and used for real-time correction during the experiment.

[0052] When the optical power attenuation is greater than 2dB, the self-calibration module sends an alarm message "fiber optic or connector failure" to the LabVIEW control platform through the software interface; when the signal-to-noise ratio is less than 25dB, the self-calibration module automatically marks the hardware address code of the failed channel, sends an alarm message "sensor failure" to the LabVIEW control platform through the software interface, and automatically removes the data of that channel.

[0053] Preferably, the energy module and interface module include:

[0054] The energy module is powered by external mains power from the shielded chamber, which is then filtered before being supplied to the optoelectronic integrated module. There is no battery inside the device under test.

[0055] The interface module includes a plastic fiber optic patch cord, an SMA-905 plastic fiber optic connector, and a bulkhead sealing structure. The plastic fiber optic patch cord transmits optical signals between the inside and outside of the shielded chamber via the SMA-905 plastic fiber optic connector. The bulkhead sealing structure is located at the through-hole on the shielded chamber wall through which the plastic fiber optic patch cord passes. It includes a rubber O-ring, a grounding spring, a sealing sleeve, and a hexagonal nut for sealing and electromagnetic shielding. The sealing sleeve is fitted onto the outer shell of the plastic fiber optic patch cord, and the rubber O-ring is fitted onto the sealing sleeve, pressing against the inner wall of the bulkhead through-hole for radial sealing. The grounding spring is fitted onto the sealing sleeve and makes tight contact with both the outer wall of the sealing sleeve and the inner wall of the bulkhead through-hole for electromagnetic shielding. The hexagonal nut is screwed onto the sealing sleeve from the outside of the shielded chamber, axially pressing the rubber O-ring and grounding spring to complete the final sealing and locking. The outer shell of the plastic fiber optic patch cord passes through the center hole of the compaction field turntable and connects to the shielding mesh of the laboratory floor. The outer diameter of the plastic fiber optic cable does not exceed 3 mm. mm, can pass through the center hole of the compact field turntable, and the optical fiber is not stretched or has additional attenuation when the turntable rotates ±180°.

[0056] The beneficial effects of this invention are as follows: by employing a conformally bonded modulated microstrip with all-fiber optics, metal-free penetration into the chamber is achieved, without compromising shielding integrity or altering the original configuration of the test specimen, thus solving the problems of interference introduced by external metal probes and structural damage caused by traditional sensors; by using single-fiber cascades, high-resolution distributed measurement of the internal electric field of the test specimen is achieved without affecting its mass distribution; integrated one-click remote self-calibration and real-time temperature decoupling functions are implemented, with an extended uncertainty ≤3% (k=2), which is better than the accuracy requirement of ≤5% in GJB 8848-2023, solving the problems of lack of automatic calibration and high uncertainty in traditional systems; the entire installation or disassembly process can be completed within 5 minutes, and the system can be reused more than 100 times, significantly improving experimental efficiency and reducing laboratory operating costs; through the design of thin-diameter optical cables, it can seamlessly adapt to various laboratory HPM environments such as compact fields, TEM chambers, and GTEM chambers, possessing excellent platform versatility.

[0057] Furthermore, the design principle of this invention is reliable, the structure is simple, and it has a very wide range of application prospects.

[0058] Therefore, it is evident that the present invention has outstanding substantive features and significant progress compared with the prior art, and the beneficial effects of its implementation are also obvious. Attached Figure Description

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0060] Figure 1 This is a flowchart of the test method for the built-in conformal fiber electric field sensor array provided by the present invention.

[0061] Figure 2 This is a schematic line drawing of the overall layout of the laboratory system provided by the present invention.

[0062] Figure 3 This is a line drawing of the conformal fiber electric field sensor array provided by the present invention.

[0063] Figure 4 This is a line drawing of the AA cross-section of the sensor provided by the present invention.

[0064] Figure 5 This is a line drawing of the self-calibration module for the micro-patch TEM chamber provided by the present invention.

[0065] Figure 6 This is a line drawing of the plastic optical fiber cabin wall sealing structure provided by the present invention.

[0066] Figure 7 This is a 5-minute rapid assembly / disassembly flowchart provided by the present invention.

[0067] 1-Test body, 2-Compressed field turntable, 3-Optical integrated module, 4-Plastic optical fiber, 5-LAN interface, 6-Data acquisition system, 7-Optical integrated chassis, 8-FBG temperature reference plate, 9-PM1550 polarization-maintaining fiber, 10-Conformal fiber electric field sensor, 11-LiNbO3 thin film electro-optic modulation microstrip, 12-Inner wall of the test body, 13-SMA-905 plastic optical fiber connector, 14-Rubber O-ring, 15-Grounding spring, 16-Sealing sleeve, 17-Top electrode, 18-Bottom electrode, 19-Air cavity, 20-PIN pin, 21-GND pin, 22-PES shield, 23-Polyimide substrate, 24-Partial magnified view of the electrode, 25-Hexagonal nut. Detailed Implementation

[0068] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. The following embodiments are explanations of the present invention, but the present invention is not limited to the following implementation methods.

[0069] Example 1:

[0070] like Figure 1 As shown, this embodiment provides a test method for a built-in conformal fiber electric field sensor array, which performs HPM irradiation experiments on an object in a compressed field. The test object 1 is horizontally fixed to a support, 5m away from the aperture of the radiation source. A 1m diameter TEM horn antenna is used as the radiation source, generating a high-power microwave pulse with a peak field strength of 50kV / m, a center frequency of 3GHz, and a pulse width of 1μs. Twenty electric field probes are arranged on the surface of the test object 1 and in the surrounding space for synchronous sampling. The measured maximum field strength is 51.2 kV / m, and the pulse rise time is 0.85 ns. The method includes the following steps:

[0071] Step S1, the preparatory steps before implementation, in which:

[0072] Positioning of test subject 1; self-testing of conformal fiber electric field sensor array; alignment of edge nodes and time reference of conformal fiber electric field sensor 10.

[0073] Step S2, the quick assembly / disassembly step, in which:

[0074] On the fixed test body 1, a conformal fiber electric field sensor array is attached, passing through plastic fiber 4, and the fiber jumper of plastic fiber 4 is connected to optoelectronic integrated chassis 7 outside the shielded chamber; remote one-click self-calibration is performed, and the data channel is checked.

[0075] Step S3, the real-time measurement and closed-loop procedure, in which:

[0076] After the experiment begins, it enters a real-time measurement state to collect electric field data, processes the data through edge GPU nodes, and finally visualizes it in real time through WebGL.

[0077] Step S4, the result confirmation and log upload step, in which:

[0078] After a single test, the measured electric field distribution was compared and automatically verified with the results of a pre-conducted CST simulation (CST Studio Suite professional three-dimensional electromagnetic field simulation software), and the overall field distribution error was found to be less than 4%.

[0079] The system automatically generates a CSV file (containing information such as initial frequency, measured electric field, error, time consumption, and timestamp) and uploads it to the web server. It uses hash-based blockchain technology for evidence storage to prevent data tampering.

[0080] Step S5, the preparation steps for the next round of experiments, in which:

[0081] The system resets the initial frequency parameters, measured electric field parameters, error parameters, time consumption parameters, timestamp parameters, and other parameters for the stepper motor; it automatically completes sensor zeroing, archives the previous round of experimental logs, and starts the test readiness process for the new round.

[0082] Step S1 specifically includes:

[0083] Position the test specimen and fix it horizontally to the compression field support to ensure that it has sufficient vibration resistance (greater than 30g) and ensure that no metal cables pass through the shielded cabin wall.

[0084] A conformal fiber electric field sensor array self-test was performed, and the electric field amplitude was collected at a spatial density of no less than 20 points / meter to obtain the detection data. The detection data was then fed back to the edge GPU node through a link combining plastic optical fiber and CAN-FD, with no metal penetration throughout the process.

[0085] By using the White-Rabbit clock synchronization protocol, the time reference of the edge GPU node is aligned to within 1 ns with all conformal fiber electric field sensors, ensuring strict synchronization of multi-channel acquired data.

[0086] Step S2 specifically includes:

[0087] like Figure 7 The rapid assembly and disassembly process is shown in the figure: the conformal fiber electric field sensor array is attached to the inner wall 12 curved surface of the test body in one go using thermally conductive adhesive, which takes 30 seconds;

[0088] Lay out and pass through a single plastic optical fiber 4 (outer diameter not exceeding 3 mm), tighten the chamber sealing sleeve to ensure shielding integrity, with no metal parts throughout the process, which takes 150 seconds;

[0089] Outside the shielded enclosure, the fiber optic patch cord of the plastic fiber 4 is connected to the optoelectronic integrated chassis 7 using the SMA-905 plastic fiber optic connector 13, which takes 30 seconds.

[0090] One-click self-calibration can be triggered remotely via the web interface to automatically complete the calibration of the built-in conformal fiber electric field sensor array, which takes 30 seconds.

[0091] Automatically checking the connectivity and signal quality of all data channels takes 30 seconds;

[0092] If the calibration and automatic checks are successful, the experiment is ready and the HPM irradiation test can be started immediately (the disassembly process is performed in reverse order, with the same efficiency).

[0093] The aforementioned method of remotely triggering one-click self-calibration via a web interface to automatically complete the calibration of the conformal fiber electric field sensor array specifically includes:

[0094] After self-calibration is initiated, a standard (1 GHz, 50 V / m) square wave calibration field is generated in the miniature patch TEM cell integrated into the inner wall of the test chamber. The responses of all conformal fiber electric field sensors are acquired, the calibration coefficients of each channel are calculated, including the gain coefficient and the offset coefficient, and directly written into the internal RAM of the FPGA phase-locked demodulation circuit for real-time correction during the experiment.

[0095] The FBG temperature reference chip 8 performs synchronous sampling at 1kHz. The temperature change ΔT is calculated based on the temperature sensitivity coefficient of the reflected wavelength change ΔλB of the FBG temperature reference chip 8. When the temperature change ΔT is less than 5℃, automatic temperature compensation is applied to the electric field measurement value to achieve temperature-electric field decoupling. The temperature sensitivity coefficient of LiNbO3 is pre-stored in the FPGA phase-locked demodulation circuit. The change in the original electric field measured on the electro-optic modulated microstrip 11 of LiNbO3 thin film Real-time correction is performed to obtain the decoupled electric field value. The corrected formula is: .

[0096] Step S3 specifically includes:

[0097] Electric field acquisition is performed by electro-optically modulating the microstrip 11 of the LiNbO3 thin film to sense changes in the electric field, and the signal is transmitted through a single PM1550 polarization-maintaining fiber 9 (without fusion splices and a loss of less than 0.2 dB).

[0098] Edge GPU processing is performed. Edge GPU nodes receive data, perform parallel computation, and share video memory through WebGL for voxelization and VolumeRayCaster volume rendering (the entire processing and rendering latency is less than 100 milliseconds). The entire process is guaranteed by the White-Rabbit clock (timestamp accuracy is better than 1 ns).

[0099] It performs real-time visualization using WebGL, processes the generated electric field distribution data, performs volume rendering using WebGL 2.0 technology, and outputs the data to a web interface, supporting real-time observation through multiple interactive modes such as mouse, touch screen, and VR headset.

[0100] In this embodiment, the above steps were repeatedly verified, and the same set of conformal fiber electric field sensors completed 120 HPM experiments (peak value 60 kV / m). The experimental results showed that the LiNbO3 thin film electro-optic modulated microstrip had no cracks, the optical insertion loss increased by less than 0.2 dB, the calibration coefficient drift was less than 1.5%, and the preparation time for a single experiment did not exceed 5 minutes (including installation, calibration, and inspection).

[0101] Example 2:

[0102] like Figure 2 As shown, this embodiment provides a test system for a built-in conformal fiber electric field sensor array, comprising:

[0103] Completely integrated within the test specimen, with no metal feed lines protruding from the test piece, it can be installed or disassembled within 5 minutes and can be reused at least 100 times. Specifically, it includes: a conformal fiber electric field sensor array, a fiber optic link module, an optoelectronic integration module, a self-calibration module, an energy module, and an interface module.

[0104] The fiber optic link module uses a single PM1550 polarization-maintaining fiber 9 connected in series with all conformal fiber electric field sensors 10 to form a conformal fiber electric field sensor array without fusion splices. The tail end of the PM1550 polarization-maintaining fiber 9 is connected to the fiber optic patch cord of the plastic fiber 4 via an SMA-905 plastic fiber connector 13. The fiber optic patch cord of the plastic fiber 4 passes through the shielded chamber and connects to the optoelectronic integrated chassis 7 (using a 1U 19″ standard chassis). The optoelectronic integrated module is integrated into the optoelectronic integrated chassis 7. The self-calibration module uses a miniature patch TEM chamber, which is bonded to the curved surface of the inner wall 12 of the test chamber with peelable thermally conductive adhesive. The energy module provides power to the optoelectronic integrated module. The interface module uses a chamber wall sealing structure to ensure the electromagnetic shielding integrity and airtightness at the point where the plastic fiber passes through the chamber.

[0105] The conformal fiber electric field sensor array includes:

[0106] Multiple LiNbO3 thin film electro-optic modulated microstrips 11, such as Figure 3As shown, the LiNbO3 thin film electro-optic modulation microstrip 11 is bonded to the curved surface of the inner wall 12 of the test body using a peelable thermally conductive adhesive and conforms to the inner wall. Under laboratory conditions, the sensitivity exceeds 0.4mV / (V / m), the range exceeds 100 kV / m, the bandwidth is DC-18 GHz, and the rise time is less than 1 ns. The conformal fiber electric field sensor array has a total length of 50 mm and adopts a spiral measurement chain layout, covering three typical areas: the first cabin, the middle cabin, and the stern cabin, with a measurement point density of more than 20 points / meter.

[0107] The LiNbO3 thin-film electro-optic modulation microstrip 11 has dimensions of 0.3 mm × 5 mm × 15 μm, a sensitivity exceeding 0.4 mV / (V / m) under laboratory conditions, a range exceeding 100 kV / m, a working bandwidth of DC-18 GHz, and a rise time of less than 1 ns. The LiNbO3 thin-film electro-optic modulation microstrip 11 is integrally formed by ion slicing and dry etching processes, and its film thickness is less than 600 nanometers, enabling conformal mounting.

[0108] The LiNbO3 thin-film electro-optic modulated microstrip 11 and the conformal fiber electric field sensor array meet the following specifications: after undergoing no less than 120 high-power microwave irradiation experiments with a peak field strength of no less than 60 kV / m, the LiNbO3 thin-film electro-optic modulated microstrip 11 shows no cracks; the optical insertion loss increases by less than 0.2 dB; and the sensor calibration coefficient drift is less than 1.5%.

[0109] like Figure 4 As shown, the LiNbO3 thin film electro-optic modulation microstrip 11 provided in this embodiment is based on the sidewall of PM1550 polarization-maintaining fiber or Si / SiO2-LNOI; the surface of the LiNbO3 thin film electro-optic modulation microstrip 11 is provided with a PES shield 22 for electromagnetic shielding and mechanical protection; the bottom of the LiNbO3 thin film electro-optic modulation microstrip 11 is made of a polyimide substrate for bottom support and electrical isolation; microelectrodes (as shown in Figure 24, where the electrodes are partially enlarged) are provided at both ends of the LiNbO3 thin film electro-optic modulation microstrip 11 for feeding electrical signals.

[0110] The fiber optic link module includes:

[0111] An FBG temperature reference sheet 8 (fiber Bragg grating temperature reference sheet) with a thickness of less than 50 μm is attached at the same position as the LiNbO3 thin film electro-optic modulation microstrip 11. The temperature sensitivity is about 10 pm / ℃ and it is used for automatic temperature decoupling correction when ΔT < 5 ℃. The core function of the FBG temperature reference sheet 8 is to provide a temperature reference for the conformal fiber electric field sensor in real time and purely optically without destroying the electric field measurement, thereby decoupling the interference of temperature on the electric field reading.

[0112] The PM1550 polarization-maintaining fiber 9 is passed through the laboratory floor grounding shielding mesh via an SMA-905 plastic fiber optic connector 13 without compromising the integrity of the shielding chamber.

[0113] The aforementioned optoelectronic integrated module includes:

[0114] DFB laser, balanced detector, FPGA phase-locked demodulation circuit; DFB laser, balanced detector, FPGA phase-locked demodulation circuit are electrically connected in sequence;

[0115] The DFB laser (a single-mode semiconductor laser with a built-in distributed feedback grating) serves as the core light source component of the optoelectronic integrated module, generating an optical signal with a wavelength of 1550 nm and a linewidth of less than 1 MHz. The DFB laser is the core light source component of the optoelectronic integrated module. The optical signal generated by the DFB laser is transmitted via plastic optical fiber 4 to a LiNbO3 thin-film electro-optic modulation microstrip 11 located in the shielded chamber for electro-optic modulation, generating a weak optical signal. The balanced detector has a common-mode rejection ratio greater than 40 dB and is responsible for converting the weak optical signal generated by the LiNbO3 thin-film electro-optic modulation microstrip 11 into a voltage signal with high fidelity and outputting it for FPGA phase-locked demodulation. The FPGA phase-locked demodulation circuit supports a 1 kHz sampling rate and has a self-calibration stage processing delay of less than 50 ms. It is responsible for receiving the voltage signal output by the balanced detector and implementing calibration coefficient writing, temperature-electric field decoupling, and fault channel marking functions.

[0116] The optoelectronic integrated module has an embedded web server that connects to the laboratory data acquisition system 6 via LAN interface 5, enabling remote one-click start, calibration, fault marking, and data download.

[0117] The self-calibration module includes:

[0118] A miniature patch TEM cell, no larger than 40 mm × 20 mm × 2 mm, is bonded to the 12-curved surface of the inner wall of the test chamber, conformally positioned to the conformal fiber electric field sensor. Figure 5 As shown, the micro-patch TEM chamber provided in this embodiment includes a top electrode 17 and a bottom electrode 18 that are parallel to each other, with an air cavity 19 with a thickness of 2 mm between them; the center feed point of the top electrode 17 is connected to the PIN pin 20 to input a calibration signal, and the ground terminal of the bottom electrode 18 is connected to the GND pin 21.

[0119] The miniature patch TEM cell generates a 1 GHz / 50 V / m square wave calibration field for automatic calibration before the experiment. The calibration time for a single channel is less than 50 ms. The calibration coefficients obtained by automatic calibration will be stored in the FPGA phase-locked demodulation circuit and used for real-time correction during the experiment.

[0120] When the optical power attenuation is greater than 2dB, the self-calibration module sends an alarm message "fiber optic or connector failure" to the LabVIEW control platform through the software interface; when the signal-to-noise ratio is less than 25dB, the self-calibration module automatically marks the hardware address code of the failed channel, sends an alarm message "sensor failure" to the LabVIEW control platform through the software interface, and automatically removes the data of that channel.

[0121] The energy module and interface module include:

[0122] The energy module is powered by external mains power from the shielded chamber, which is then filtered before being supplied to the optoelectronic integrated module. There is no battery inside the device under test.

[0123] like Figure 6 As shown, the interface module includes a plastic fiber optic patch cord, an SMA-905 plastic fiber optic connector 13, and a bulkhead sealing structure. The plastic fiber optic patch cord transmits optical signals between the inside and outside of the shielded compartment via the SMA-905 plastic fiber optic connector 13. The bulkhead sealing structure is located on the shielded compartment wall at the through-hole through which the plastic fiber optic patch cord passes, and includes a rubber O-ring 14, a grounding spring 15, a sealing sleeve 16, and a hexagonal nut 25 for sealing and electromagnetic shielding. The sealing sleeve 16 is fitted onto the outer shell of the plastic fiber optic patch cord. Rubber O-ring 14 is fitted onto sealing sleeve 16 and pressed against the inner wall of the bulkhead through hole to achieve radial sealing. Grounding spring 15 is fitted onto sealing sleeve 16 and makes tight contact with the outer wall of sealing sleeve 16 and the inner wall of bulkhead through hole to achieve electromagnetic shielding connection. Hexagonal nut 25 is screwed onto sealing sleeve 16 from the outside of shielding chamber to axially press rubber O-ring 14 and grounding spring 15 to complete final sealing and locking. The outer shell of plastic optical fiber jumper passes through the central hole of compaction field turntable 2 and is connected to the shielding mesh of laboratory floor. The outer diameter of plastic optical fiber 4 does not exceed 3 mm and can pass through the central hole of compaction field turntable 2. When compaction field turntable 2 rotates ±180°, plastic optical fiber 4 has no stretching and no additional attenuation.

[0124] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The methods disclosed in the embodiments are described simply because they correspond to the systems disclosed in the embodiments; relevant details can be found in the method section.

[0125] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0126] In the embodiments provided by this invention, it should be understood that the disclosed systems, methods, and approaches can be implemented in other ways. For example, the system embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between systems or units may be electrical, mechanical, or other forms.

[0127] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0128] In addition, the functional modules in the various embodiments of the present invention can be integrated into one processing unit, or each module can exist physically separately, or two or more modules can be integrated into one unit.

[0129] Similarly, in the various embodiments of the present invention, each processing unit can be integrated into a functional module, or each processing unit can exist physically, or two or more processing units can be integrated into a functional module.

[0130] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0131] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0132] The above-disclosed embodiments are merely preferred embodiments of the present invention, but the present invention is not limited thereto. Any non-creative variations that can be conceived by those skilled in the art, as well as any improvements and modifications made without departing from the principles of the present invention, should fall within the protection scope of the present invention.

Claims

1. A test system with a built-in conformal fiber electric field sensor array, characterized in that, include: Conformal fiber electric field sensor array, fiber optic link module, optoelectronic integration module, self-calibration module, energy module, interface module; The fiber optic link module uses a single PM1550 polarization-maintaining fiber to connect all conformal fiber electric field sensors in series, forming a conformal fiber electric field sensor array without fusion splices. The tail of the PM1550 polarization-maintaining fiber is connected to a fiber optic patch cord of a plastic fiber via an SMA-905 plastic fiber connector. The fiber optic patch cord of the plastic fiber passes through the shielded chamber and connects to the optoelectronic integrated chassis. The optoelectronic integrated module is integrated into the optoelectronic integrated chassis. The self-calibration module uses a miniature patch TEM chamber, which is bonded to the curved surface of the inner wall of the test chamber with peelable thermally conductive adhesive. The energy module provides power to the optoelectronic integrated module, and the interface module adopts a chamber wall sealed structure. The conformal fiber electric field sensor array includes: Multiple LiNbO3 thin-film electro-optic modulated microstrips are attached to the curved surface of the inner wall of the test chamber using a peelable thermally conductive adhesive and conform to the inner wall. The conformal fiber electric field sensor array has a total length of 50 mm and adopts a spiral measurement chain layout to cover three typical areas: the first chamber, the middle chamber, and the stern chamber, with a measurement point density of more than 20 points / meter. The LiNbO3 thin-film electro-optic modulation microstrip has dimensions of 0.3 mm × 5 mm × 15 μm, a sensitivity of no less than 0.4 mV / (V / m) under laboratory conditions, an electric field measurement range greater than 100 kV / m, a working bandwidth of DC-18 GHz, and a rise time of less than 1 ns. The LiNbO3 thin-film electro-optic modulation microstrip is integrally formed by ion slicing and dry etching processes, and its film thickness is less than 600 nanometers. The LiNbO3 thin-film electro-optic modulated microstrip and conformal fiber electric field sensor array meet the following specifications: after undergoing at least 120 high-power microwave irradiation experiments with a peak field strength of not less than 60 kV / m, the LiNbO3 thin-film electro-optic modulated microstrip shows no cracks; the increase in optical insertion loss is less than 0.2 dB; and the sensor calibration coefficient drift is less than 1.5%. The fiber optic link module includes: An FBG temperature reference sheet with a thickness of less than 50 μm is attached to the same position as the LiNbO3 thin film electro-optic modulation microstrip. The temperature sensitivity is 10 pm / ℃, the response speed is less than 1 ms, and it supports 1 kHz synchronous sampling. It is used for automatic temperature decoupling correction when ΔT < 5 ℃. The PM1550 polarization-maintaining fiber optic tail passes through the laboratory floor grounding shielding mesh via an SMA-905 plastic fiber optic connector, without compromising the integrity of the shielding chamber. The self-calibration module includes: The miniature patch TEM cell, measuring less than 40 mm × 20 mm × 2 mm, is bonded to the inner curved surface of the test chamber with a peelable thermally conductive adhesive, and is conformally aligned with the conformal fiber electric field sensor.

2. The built-in conformal fiber electric field sensor array test system according to claim 1, characterized in that, The aforementioned optoelectronic integrated module includes: DFB laser, balanced detector, FPGA phase-locked demodulation circuit; The DFB laser, as the core light source component of the optoelectronic integrated module, generates optical signals with a wavelength of 1550nm and a linewidth of less than 1 MHz. The optical signal generated by the DFB laser is transmitted through a plastic optical fiber to the LiNbO3 thin film electro-optic modulation microstrip located in the shielded chamber for electro-optic modulation, generating a weak optical signal. The balanced detector has a common-mode rejection ratio greater than 40dB and is responsible for converting the weak optical signal generated by the LiNbO3 thin film electro-optic modulated microstrip into a voltage signal and outputting it with high fidelity. The FPGA phase-locked demodulation circuit supports a 1 kHz sampling rate and has a self-calibration processing delay of less than 50 ms. It is responsible for receiving the voltage signal output by the balanced detector and implementing calibration coefficient writing, temperature-electric field decoupling, and fault channel marking functions. The optoelectronic integrated module has an embedded web server that connects to the laboratory data acquisition system via a LAN interface, enabling remote one-click start, calibration, fault marking, and data download.

3. The built-in conformal fiber electric field sensor array test system according to claim 1, characterized in that, The self-calibration module includes: The miniature patch TEM cell generates a 1 GHz / 50 V / m square wave calibration field for automatic calibration before the experiment. The calibration time for a single channel is less than 50 ms. The calibration coefficients obtained by automatic calibration will be stored in the FPGA phase-locked demodulation circuit and used for real-time correction during the experiment. When the optical power attenuation is greater than 2dB, the self-calibration module sends an alarm message "fiber optic or connector failure" to the LabVIEW control platform through the software interface; when the signal-to-noise ratio is less than 25dB, the self-calibration module automatically marks the hardware address code of the failed channel, sends an alarm message "sensor failure" to the LabVIEW control platform through the software interface, and automatically removes the data of that channel.

4. The built-in conformal fiber electric field sensor array test system according to claim 1, characterized in that, The energy module and interface module include: The energy module is powered by external mains power from the shielded chamber, which is then filtered before being supplied to the optoelectronic integrated module. There is no battery inside the device under test. The interface module includes a plastic fiber optic patch cord, an SMA-905 plastic fiber optic connector, and a bulkhead sealing structure. Among them, the plastic fiber optic patch cord uses the SMA-905 plastic fiber optic connector to achieve optical signal transmission inside and outside the shielded cabin; The bulkhead sealing structure is located at the through-hole on the shielded bulkhead through which the fiber optic patch cord of the plastic optical fiber passes. It includes a rubber O-ring, a grounding spring, a sealing sleeve, and a hexagonal nut to achieve sealing and electromagnetic shielding. The sealing sleeve is fitted onto the fiber optic patch cord housing of the plastic optical fiber. The rubber O-ring is fitted onto the sealing sleeve and pressed against the inner wall of the bulkhead through hole to achieve radial sealing. The grounding spring is fitted onto the sealing sleeve and makes tight contact with the outer wall of the sealing sleeve and the inner wall of the bulkhead through hole to achieve electromagnetic shielding connection. The hexagonal nut is screwed onto the sealing sleeve from the outside of the shielding chamber to axially press the rubber O-ring and the grounding spring. After the fiber optic patch cord sheath of the plastic optical fiber passes through the central hole of the compaction turntable, it is connected to the shielding mesh of the laboratory floor.

5. A test method for a built-in conformal fiber electric field sensor array, the method being applicable to the test system for a built-in conformal fiber electric field sensor array as described in any one of claims 1-4, characterized in that, Includes the following steps: Step S1, the preparatory steps before implementation, in which: Perform test object positioning; perform self-testing on the conformal fiber electric field sensor array; align the edge nodes and the time reference of the conformal fiber electric field sensor. Step S2, the quick assembly / disassembly step, in which: A conformal fiber electric field sensor array was attached to the fixed test body, through which plastic optical fibers were passed, and fiber jumpers were connected to the optoelectronic integrated chassis outside the shielded chamber. Perform remote one-click self-calibration and check the data channel; Step S3, the real-time measurement and closed-loop procedure, in which: After the experiment begins, it enters real-time measurement mode to collect electric field data, processes the data through edge GPU nodes, and finally visualizes it in real time through WebGL. Step S4, the result confirmation and log upload step, in which: After a single test, the measured electric field distribution is compared with the pre-performed CST simulation results and automatically verified. Automatically generate a CSV file and upload it to the web server, using hash-based blockchain technology for evidence storage; Step S5, the preparation steps for the next round of experiments, in which: Reset the initial frequency parameters, measured electric field parameters, error parameters, time consumption parameters, and timestamp parameters for the stepper motor; The system automatically completes sensor zeroing, archives the previous round of experimental logs, and initiates the preparation process for the new round of experiments.

6. The test method for the built-in conformal fiber electric field sensor array according to claim 5, characterized in that, Step S1 specifically includes: Position the test specimen by horizontally fixing the multimode test specimen to the compression field support, ensuring that no metal cables pass through the shielded chamber wall; Perform a self-test on the conformal fiber electric field sensor array, and collect the electric field amplitude at a spatial density of no less than 20 points / meter to obtain the detection data; The detection data is fed back to the edge GPU node via a link combining plastic optical fiber and CAN-FD, with no metal penetrating the cabin throughout the process; The White-Rabbit clock synchronization protocol aligns the time base of edge GPU nodes with that of all conformal fiber electric field sensors to within 1 ns.

7. The testing method for the built-in conformal fiber electric field sensor array according to claim 5, characterized in that, Step S2 specifically includes: The conformal fiber electric field sensor array was bonded to the curved surface of the inner wall of the test chamber in one step using thermally conductive adhesive. A single plastic optical fiber is laid and threaded through it. The outer diameter of the plastic optical fiber does not exceed 3 mm. The sealing sleeve for the passage is tightened. There are no metal parts throughout the entire process. Outside the shielded enclosure, use SMA-905 plastic fiber optic connectors to connect the plastic fiber optic patch cords to the optoelectronic integrated chassis. One-click self-calibration can be triggered remotely via the web interface to automatically complete the calibration of the built-in conformal fiber electric field sensor array; Automatically check the connectivity and signal quality of all data channels; If the calibration and automatic checks are successful, the experiment is ready and the HPM irradiation test can be started immediately. The aforementioned method of remotely triggering one-click self-calibration via a web interface to automatically complete the calibration of the conformal fiber electric field sensor array specifically includes: After self-calibration is initiated, the micro-patch TEM chamber integrated into the inner wall of the test chamber generates a standard 1 GHz, 50 V / m square wave calibration field. The responses of all conformal fiber electric field sensors are collected, the calibration coefficients of each channel are calculated, including the gain coefficient and the offset coefficient, and directly written into the internal RAM of the FPGA phase-locked demodulation circuit for real-time correction during the experiment. The FBG temperature reference chip performs synchronous sampling at 1kHz. The temperature change ΔT is calculated based on the temperature sensitivity coefficient of the reflected wavelength change ΔλB of the FBG temperature reference chip. When the temperature change ΔT is less than 5℃, automatic temperature compensation is applied to the electric field measurement value to achieve temperature-electric field decoupling. The temperature sensitivity coefficient of LiNbO3 is pre-stored in the FPGA phase-locked demodulation circuit. The change in the original electric field measured on the LiNbO3 microstrip Real-time correction is performed to obtain the decoupled electric field value. The corrected formula is: .

8. The test method for the built-in conformal fiber electric field sensor array according to claim 5, characterized in that, Step S3 specifically includes: Electric field acquisition is performed by electro-optic modulation of the LiNbO3 thin film to induce changes in the electric field of the microstrip sensor, and the signal is transmitted through a single PM1550 polarization-maintaining fiber. Edge GPU processing is performed. Edge GPU nodes receive data, perform parallel computation, and share video memory through WebGL for voxelization and VolumeRayCaster volume rendering. The entire process is guaranteed by the White-Rabbit clock to ensure time accuracy. It performs real-time visualization using WebGL, processes the generated electric field distribution data, performs volume rendering using WebGL 2.0 technology, and outputs the data to a web interface, supporting real-time observation via mouse interaction, touchscreen interaction, and VR headset interaction.

Images