Terahertz defect detection device based on multiple-input multiple-output array
By employing a terahertz defect detection device based on a multi-input multi-output array and using staggered array arrangement and all-electronic technology, the problems of low efficiency and slow imaging speed in composite material detection have been solved, achieving rapid, non-destructive, and accurate defect detection.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CHINA ELECTRONIS TECH INSTR CO LTD
- Filing Date
- 2026-02-12
- Publication Date
- 2026-05-12
AI Technical Summary
Existing nondestructive testing methods for detecting defects in composite materials suffer from problems such as low efficiency, difficulty in detecting complex structures, material contamination or electromagnetic radiation during the testing process, and slow imaging speed and strict environmental requirements for terahertz defect detection.
A terahertz defect detection device based on a multi-input multi-output array is adopted, including a gantry, a transmission table, a defect detection array front end, a microwave signal generation module, and a data acquisition and control module. It utilizes a terahertz signal generation array, a receiving array, and a transceiver antenna module, and adopts an interleaved array arrangement and all-electronic high-frequency band technology, combined with a large beamwidth pyramidal horn antenna, to achieve rapid and non-destructive testing.
It enables rapid, efficient, and non-destructive testing of defects in composite materials, improves imaging speed and resolution, reduces system cost and environmental requirements, and enhances detection accuracy and dynamic range.
Smart Images
Figure CN122016705A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of testing technology, and specifically to a terahertz defect detection device based on a multi-input multi-output array. Background Technology
[0002] The terahertz band is an electromagnetic frequency band located between the microwave and infrared regions of the electromagnetic spectrum. Due to the unique advantages of terahertz waves, such as rich information carrying capacity, low photon energy, high spatiotemporal coherence, and high safety in use, it has attracted widespread attention from technicians in the field of nondestructive testing technology in recent years, especially in the imaging and defect detection of composite material structures.
[0003] Defect detection and quality monitoring during the preparation and use of non-metallic materials such as composite materials and polymers have become indispensable and crucial aspects. The presence of defects can affect the service life of material components and even cause complete structural damage. Therefore, it is necessary to quickly and accurately detect defects in material components to determine the location, type, and extent of damage within the components.
[0004] Currently, commonly used nondestructive testing methods for material defects mainly include ultrasonic and radiographic testing. However, traditional testing methods for various composite materials have certain limitations. For example, ultrasonic testing suffers from low efficiency, difficulty in testing complex structures, and material contamination caused by the coupling agent used during the testing process. Radiographic testing has limitations in detecting crack-type defects and generates electromagnetic radiation that is harmful to the human body. Furthermore, most existing terahertz defect detection imaging systems are based on optical sources, which are limited by the long scanning time of the testing mechanism, resulting in slow imaging speed, low imaging efficiency, and a low dynamic range, leading to generally poor image quality for material defect detection. Moreover, the high-precision optical equipment used in current nondestructive testing of material defects has strict environmental requirements, while terahertz defect detection devices utilize terahertz multi-input multi-output arrays, which offer fast imaging speeds and lower environmental requirements.
[0005] Therefore, there is an urgent need to propose a terahertz defect detection device based on a multi-input multi-output array to achieve rapid and efficient non-destructive testing of material defects. Summary of the Invention
[0006] To address the aforementioned technical problems, this invention provides a terahertz defect detection device based on a multi-input multi-output array. This device features high integration, system stability, and high imaging efficiency, enabling rapid, efficient, and non-destructive detection of defects in non-metallic materials and providing technical support for defect analysis of non-metallic materials.
[0007] The technical solution adopted in this invention is: A terahertz defect detection device based on a multiple-input multiple-output array includes a gantry, a transmission stage, a defect detection array front end, a microwave signal generation module, and a data acquisition and control module. The defect detection array front end is fixed on the gantry and connected to the microwave signal generation module. The transmission stage is used to place the sample to be tested and is located below the defect detection array front end. The gantry, transmission stage, defect detection array front end, and microwave signal generation module are all connected to the data acquisition and control module.
[0008] Preferably, the front end of the defect detection array is provided with a terahertz signal generating array, a terahertz signal receiving array, and a transceiver antenna module for detecting defects in the sample under test. The microwave signal generation module includes a signal generating device, a first power divider, a second power divider, and a reference signal module. The signal generating device generates microwave radio frequency (RF) signals and microwave local oscillator (LO) signals. The RF signals are input to the first power divider, and the LO signals are input to the second power divider. The first power divider splits the RF signals into two paths: one path is input to a multi-channel terahertz signal generating array as the RF excitation signal for each terahertz signal generating channel, and the other path is input to the reference signal module as the RF excitation signal for the reference signal module. The second power divider splits the LO signals into two paths: one path is input to a multi-channel terahertz signal receiving array as the LO excitation signal for each terahertz signal receiving channel, and the other path is input to the reference signal module as the LO excitation signal for the reference signal module. The reference signal module generates a reference signal to calibrate the phase difference between the RF excitation signal and the LO excitation signal. The terahertz signal generating array is equipped with a first electronic switch and N terahertz signal generating channels to generate multiple terahertz radiation signals. The terahertz signal receiving array is equipped with a second electronic switch and N terahertz signal receiving channels to generate multiple intermediate frequency signals. The transceiver antenna module is connected to the terahertz signal generating array and the terahertz signal receiving array, respectively. It is equipped with 2N high-performance terahertz transceiver antennas, which are used to output the terahertz radiation signal generated by the terahertz signal generating array and to receive the terahertz echo signal in the detection space.
[0009] Preferably, the terahertz signal generating array is provided with a first electronic switch and N terahertz signal generating channels for generating multiple terahertz radiation signals, and the terahertz signal receiving array is provided with a second electronic switch and N terahertz signal receiving channels for generating multiple intermediate frequency signals. In the terahertz signal receiving array, the second electronic switch is connected to each terahertz signal receiving channel to control the connection of the terahertz signal receiving channels. The terahertz signal receiving channels generate multiple intermediate frequency signals by amplifying and multiplying the input local oscillator excitation signal and mixing it with the terahertz echo signal.
[0010] Preferably, the terahertz signal generating array and the terahertz signal receiving array are each provided with multiple array elements at equal intervals. The array elements in the terahertz signal generating array and the array elements in the terahertz signal receiving array are arranged alternately and correspond one-to-one. The array elements in the terahertz signal generating array are offset from their corresponding array elements in the terahertz signal receiving array by half an array element spacing.
[0011] Preferably, the high-performance terahertz transceiver antenna is a pyramidal horn antenna with a large beamwidth in the H-plane.
[0012] Preferably, the gantry and the transmission table together form the sample transmission platform.
[0013] Preferably, the data acquisition and control module includes a signal acquisition module and a central controller. The signal acquisition module is connected to the microwave signal generation module and the front end of the defect detection array, respectively, and is used to acquire the reference signal output by the microwave signal generation module and the multiple intermediate frequency signals output by the terahertz signal receiving array, and input them into the central controller. The central controller is connected to the microwave signal generation module, the signal acquisition module and the sample transmission platform, respectively, and is used to control the microwave signal generation module, the signal acquisition module and the sample transmission platform.
[0014] The beneficial effects of this invention are as follows: (1) This invention proposes a terahertz defect detection device based on a multi-input multi-output array, which can extract material feature information without damaging the material, and realize efficient and rapid detection of internal defects in the material.
[0015] (2) This invention proposes a terahertz defect detection device based on a multi-input multi-output array. By setting a terahertz signal generating array, a terahertz signal receiving array, and a transceiver antenna module in the front end of the defect detection array, non-destructive testing of materials can be achieved. The array arrangement scheme with staggered transceiver is adopted to set array elements in the terahertz signal generating array and the terahertz signal receiving array, which reduces the mutual coupling and crosstalk between different array element signals. Compared with the traditional aligned array arrangement scheme, it effectively ensures the sampling interval of the signal and reduces the number of array elements, reduces the redundancy of system data, and greatly improves the imaging speed of material defects.
[0016] (3) This invention proposes a terahertz defect detection device based on a multi-input multi-output array. It adopts a high-frequency, ultra-wideband terahertz signal transceiver technology with all-electronics, which effectively improves the dynamic range and signal-to-noise ratio of the terahertz defect detection device during detection. Combined with the wide bandwidth, it effectively improves the distance resolution of the terahertz defect detection device, and greatly improves the resolution and accuracy of material defect detection.
[0017] (4) This invention proposes a terahertz defect detection device based on a multi-input multi-output array. A large beamwidth pyramidal horn antenna is used in the transceiver antenna module at the front end of the defect detection array to achieve a large gain angle in the H-plane across the entire frequency band, effectively suppressing the grating sidelobe level and improving the imaging resolution of material defect detection. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of a terahertz defect detection device based on a multi-input multi-output array according to the present invention.
[0019] Figure 2 This is a schematic diagram of a terahertz defect detection device based on a multi-input multi-output array according to the present invention.
[0020] Figure 3 This is a schematic diagram of the array element arrangement of the present invention.
[0021] In the diagram, 1. Gantry, 2. Transmission table, 3. Defect detection array front end, 4. Sample to be tested, 5. System cabinet, 6. Bundled cable. Detailed Implementation
[0022] Example 1 This invention proposes a terahertz defect detection device based on a multi-input multi-output array, such as... Figures 1-2 As shown, the system includes a gantry frame 1, a transmission platform 2, a defect detection array front end 3, a microwave signal generation module, and a data acquisition and control module. The defect detection array front end is fixed to the gantry frame and connected to the microwave signal generation module. The transmission platform, located below the defect detection array front end, is used to place the sample to be tested 4. The gantry frame and transmission platform together form a sample transmission platform. The transmission platform is used to adjust the position of the sample to be tested and control its high-precision one-dimensional rapid movement. The gantry frame is used to adjust the height of the defect detection array front end and control the distance between it and the sample to be tested. The microwave signal generation module and the data acquisition and control module are integrated into a system cabinet 5. The defect detection array front end is connected to the data acquisition and control module via a bundled cable 6. The data acquisition and control module is also connected to the transmission platform, the gantry frame, and the microwave signal generation module.
[0023] Furthermore, the front end of the defect detection array is used to detect material defects in the sample to be tested, and is internally equipped with a terahertz signal generating array, a terahertz signal receiving array, and a transceiver antenna module.
[0024] The microwave signal generation module includes a signal generating device, a first power divider, a second power divider, and a reference signal module. The signal generating device generates microwave radio frequency (RF) signals and microwave local oscillator (LO) signals. The RF signals and LO signals use the same reference clock signal and transmission path, and there is a fixed frequency difference between them. The RF signals are input to the first power divider, which splits them into two paths: one path is input to a multi-channel terahertz signal generating array as the RF excitation signal for each terahertz signal generating channel; the other path is input to the reference signal module as its RF excitation signal. The LO signals are input to the second power divider, which splits them into two paths: one path is input to a multi-channel terahertz signal receiving array as the LO excitation signal for each terahertz signal receiving channel; the other path is input to the reference signal module as its LO excitation signal. The reference signal module is used to generate a reference signal and calibrate the phase difference between the radio frequency excitation signal and the local oscillator excitation signal.
[0025] Specifically, in this embodiment, the terahertz signal generating array is equipped with a first electronic switch and N terahertz signal generating channels to generate multiple terahertz radiation signals. The first electronic switch is connected to a first power divider and is used to receive control signals from the data acquisition and control module to control the selection of the N terahertz signal generating channels. Its switching speed is as fast as tens of nanometers. The terahertz signal generating channels have the same structure, including low-noise amplifiers, frequency multipliers, etc., to realize the power amplification, frequency multiplication, and filtering of the radio frequency excitation signal to generate multi-channel terahertz radiation signals.
[0026] The terahertz signal receiving array is equipped with a second electronic switch and N terahertz signal receiving channels to generate multiple intermediate frequency signals. The second electronic switch is connected to a second power divider and is used to receive control signals from the data acquisition and control module to control the selection of the N terahertz signal receiving channels. Its switching speed can reach tens of nanometers. Each terahertz signal receiving channel has the same structure, including a low-noise amplifier, a frequency multiplier, a mixer, etc., to amplify and multiply the microwave local oscillator signal and to mix and transform the terahertz echo signal to generate an intermediate frequency signal.
[0027] The transceiver antenna module is connected to both the terahertz signal generating array and the terahertz signal receiving array. It internally houses 2N high-performance terahertz transceiver antennas; that is, the terahertz signal generating array is equipped with N high-performance terahertz transceiver antennas to output the terahertz radiation signal generated by the terahertz signal generating array, and the terahertz signal receiving array is also equipped with N high-performance terahertz transceiver antennas to receive terahertz echo signals in the detection space. In this embodiment, the high-performance terahertz transceiver antenna is specifically a H-plane large-beamwidth pyramidal horn antenna, which effectively suppresses the grating sidelobe level and improves the defect detection imaging resolution.
[0028] To simplify the control of microwave signal parameters, this embodiment sets the frequency conversion factor of the terahertz signal generating array and the terahertz signal receiving array to be the same, the total number of array elements in the terahertz signal generating array and the terahertz signal receiving array to be the same, and the array elements in the terahertz signal generating array and the terahertz signal receiving array are staggered and correspond one-to-one. An array element in the terahertz signal generating array is offset from its corresponding element in the terahertz signal receiving array by half an array element spacing. Figure 3 As shown, while maintaining a signal sampling interval of Δx, the element spacing is increased to 2Δx. Since N elements are evenly spaced in both the terahertz signal generating array and the terahertz signal receiving array, there are a total of 2N-1 equivalent phase center positions. Compared to traditional transceiver array alignment design methods, the terahertz signal input / output array arrangement scheme adopted in this invention reduces the number of array elements by half under the same sampling interval, effectively saving array costs.
[0029] Furthermore, the data acquisition and control module includes a signal acquisition module and a central controller. The signal acquisition module is connected to the microwave signal generation module and the defect detection array front end, respectively, and is used to acquire the reference signal output by the microwave signal generation module and the multiple intermediate frequency signals output by the terahertz signal receiving array, and input them into the central controller. The central controller is connected to the microwave signal generation module, the signal acquisition module and the sample transmission platform, respectively. It has pre-installed terahertz defect detection device testing software. Through the data interface, it sends control commands to the microwave signal generation module, the transmission platform, the gantry and the defect detection array front end, and controls the microwave signal generation module, the defect detection array front end and the sample transmission platform to realize the material defect detection of the sample to be tested.
[0030] Specifically, in this embodiment, the terahertz defect detection software includes an amplitude-phase consistency calibration algorithm and a terahertz multiple-input multiple-output array imaging algorithm. The amplitude-phase consistency calibration algorithm is used to optimize the intermediate frequency signal acquired by the signal acquisition module, and the terahertz multiple-input multiple-output array imaging algorithm is used to acquire defect images of the sample under test.
[0031] Example 2 In this embodiment, the terahertz defect detection device based on a multi-input multi-output array described in Embodiment 1 is used for material defect detection. In this embodiment, the front end of the defect detection array of the terahertz defect detection device is fixed on the gantry, and the detection target is placed on the transmission table. The front end of the defect detection array adopts an eight-channel 0.33~0.5THz terahertz signal generating array and an eight-channel 0.33~0.5THz terahertz signal receiving array. The microwave signal generating module and the data acquisition and control module are integrated in the system cabinet. The front end of the defect detection array is connected to the central controller through a bundled cable.
[0032] The central controller is equipped with terahertz defect detection software, which is used to set the test parameters of the defect detection array front end and the sample transmission platform according to the type of sample and the defect type. Specifically, based on the characteristics of the sample, parameters such as the start frequency, end frequency, number of scan points, scan range, and scan speed are set. These parameters are controlled via the LAN port to control the signal generator in the microwave signal generation module, the first electronic switch in the terahertz signal generation array, and the second electronic switch in the terahertz signal receiving array. This ensures that each terahertz signal generation channel in the terahertz signal generation array sequentially generates terahertz signals, which are then radiated to the sample via the high-performance terahertz transceiver antenna of the transceiver antenna module. The high-performance terahertz transceiver antenna connected to the terahertz signal receiving array receives the echo signals. The echo signals are sequentially mixed by an eight-channel 0.33~0.5THz terahertz signal receiving array to generate intermediate frequency signals, which are then transmitted to the signal acquisition module and reference signal generated by the reference signal module for amplification, filtering, ratioing, digital-to-analog conversion, and other data processing. The resulting reflection characteristic data of each channel is then transmitted back to the central controller.
[0033] In this embodiment, the sample to be tested is placed on the transmission stage. Using the terahertz defect detection software of the central controller, the height of the gantry and the position of the transmission stage are adjusted according to the characteristics of the sample to be tested. The microwave signal generation module is controlled to generate microwave signals, so that the front end of the defect detection array is located 30cm to 60cm above the sample to be tested for scanning. After receiving the array scanning data returned by the front end of the defect detection array, the central controller runs the preset terahertz defect detection and optimization algorithm according to the scanning parameters and the type of the sample to be tested, so as to realize defect imaging and defect type identification of the sample to be tested.
[0034] Of course, the above description is not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the present invention should also fall within the protection scope of the present invention.
Claims
1. A terahertz defect detection device based on a multiple-input multiple-output array, characterized in that, The device includes a gantry frame, a transmission table, a defect detection array front end, a microwave signal generation module, and a data acquisition and control module. The defect detection array front end is fixed on the gantry frame and connected to the microwave signal generation module. The transmission table is used to place the sample to be tested and is located below the defect detection array front end. The gantry frame, transmission table, defect detection array front end, and microwave signal generation module are all connected to the data acquisition and control module.
2. The terahertz defect detection device based on a multi-input multi-output array according to claim 1, characterized in that, The front end of the defect detection array is equipped with a terahertz signal generating array, a terahertz signal receiving array, and a transceiver antenna module for detecting defects in the sample under test. The microwave signal generation module includes a signal generating device, a first power divider, a second power divider, and a reference signal module. The signal generating device generates microwave radio frequency (RF) signals and microwave local oscillator (LO) signals. The RF signals are input to the first power divider, and the LO signals are input to the second power divider. The first power divider splits the RF signals into two paths: one path is input to a multi-channel terahertz signal generating array as the RF excitation signal for each terahertz signal generating channel, and the other path is input to the reference signal module as the RF excitation signal for the reference signal module. The second power divider splits the LO signals into two paths: one path is input to a multi-channel terahertz signal receiving array as the LO excitation signal for each terahertz signal receiving channel, and the other path is input to the reference signal module as the LO excitation signal for the reference signal module. The reference signal module generates a reference signal to calibrate the phase difference between the RF excitation signal and the LO excitation signal. The terahertz signal generating array is equipped with a first electronic switch and N terahertz signal generating channels to generate multiple terahertz radiation signals. The terahertz signal receiving array is equipped with a second electronic switch and N terahertz signal receiving channels to generate multiple intermediate frequency signals. The transceiver antenna module is connected to the terahertz signal generating array and the terahertz signal receiving array, respectively. It is equipped with 2N high-performance terahertz transceiver antennas, which are used to output the terahertz radiation signal generated by the terahertz signal generating array and to receive the terahertz echo signal in the detection space.
3. The terahertz defect detection device based on a multi-input multi-output array according to claim 2, characterized in that, The terahertz signal generating array is equipped with a first electronic switch and N terahertz signal generating channels to generate multiple terahertz radiation signals. The terahertz signal receiving array is equipped with a second electronic switch and N terahertz signal receiving channels to generate multiple intermediate frequency signals. In the terahertz signal receiving array, the second electronic switch is connected to each terahertz signal receiving channel to control the connection of the terahertz signal receiving channels. The terahertz signal receiving channels generate multiple intermediate frequency signals by amplifying and multiplying the input local oscillator excitation signal and mixing it with the terahertz echo signal.
4. The terahertz defect detection device based on a multi-input multi-output array according to claim 3, characterized in that, The terahertz signal generating array and the terahertz signal receiving array are each provided with multiple array elements at equal intervals. The array elements in the terahertz signal generating array and the array elements in the terahertz signal receiving array are arranged alternately and correspond one-to-one. The array elements in the terahertz signal generating array are offset from their corresponding array elements in the terahertz signal receiving array by half an array element spacing.
5. The terahertz defect detection device based on a multi-input multi-output array according to claim 2, characterized in that, The high-performance terahertz transceiver antenna is a pyramidal horn antenna with a large beamwidth in the H-plane.
6. The terahertz defect detection device based on a multi-input multi-output array according to claim 1, characterized in that, The gantry and the transmission table together form the sample transmission platform.
7. The terahertz defect detection device based on a multi-input multi-output array according to claim 1, characterized in that, The data acquisition and control module includes a signal acquisition module and a central controller. The signal acquisition module is connected to the microwave signal generation module and the front end of the defect detection array, respectively, and is used to acquire the reference signal output by the microwave signal generation module and the multiple intermediate frequency signals output by the terahertz signal receiving array, and input them into the central controller. The central controller is connected to the microwave signal generation module, the signal acquisition module and the sample transmission platform, respectively, and is used to control the microwave signal generation module, the signal acquisition module and the sample transmission platform.