Antenna array support and control method thereof

Abstract

The invention belongs to but is not limited to the technical field of microwave signal detection, and particularly relates to an antenna array support and a control method thereof, and the antenna array support comprises a 64-channel antenna array which is composed of a transmitting antenna and a plurality of receiving antennas; and the antenna array bracket is used for supporting the 64-channel antenna array. And the 64-channel antenna array is connected with the 64-channel signal transmitting and receiving device through a radio frequency cable, and is fixed at a preset position by the antenna array bracket. The 64-channel antenna array and the multi-channel signal transmitting and receiving device work synchronously, and real-time collection and multi-dimensional analysis of tunnel wall reflection signals are achieved in a single-channel transmitting and multi-channel parallel receiving mode. And a uniform clock reference is provided for each channel through the clock module, so that the phase deviation and the synchronization error in the signal sampling process are greatly reduced. And meanwhile, the antenna array bracket can be flexibly fixed and the array layout can be adjusted to cover different areas of the tunnel wall, so that the detection precision and efficiency of various hidden injuries are improved.

Description

Technical Field

[0001] This invention belongs to, but is not limited to, the field of microwave signal detection technology, and particularly relates to an antenna array support and its control method. Background Technology

[0002] With societal development, non-destructive testing (NDT) technology is rapidly gaining public attention. Microwave NDT is a non-destructive testing technique that utilizes the principle of microwave-matter interaction. By analyzing phenomena such as microwave signal propagation, reflection, transmission, and scattering within materials, it detects internal defects or assesses material properties. Microwave NDT boasts advantages such as non-contact, non-destructive, high resolution, and high sensitivity. It can quickly and accurately detect internal defects in materials without damaging the object being tested, making it suitable for testing in various complex environments. As the mileage of tunnel construction in my country continues to expand, the task of tunnel quality inspection is becoming increasingly important. Therefore, efficiently conducting NDT of hidden defects in tunnel walls has become a crucial task.

[0003] Ultra-wideband (UWB) technology has wide applications in aerospace, radar, microwave imaging, and wireless communication. UWB antennas, as crucial components of UWB systems, play a vital role. Vivaldi antennas, with their advantages of ultra-wideband coverage, concentrated radiation direction, strong anti-interference capability, and ease of integration, have become one of the most widely used UWB antennas. With the rapid development of radio technology, UWB systems place higher demands on antenna bandwidth and gain. Traditional Vivaldi antennas suffer from current recirculation on the patch surface. A portion of the current flows from the inside of the exponentially tapered line to the patch edge, resulting in energy concentration, increased antenna loss, reduced gain, and poor radiation performance, making it difficult to meet practical application requirements.

[0004] Based on the above analysis, the problems and shortcomings of the existing technology are as follows: Traditional Vivaldi antennas suffer from current backflow on the patch surface. Some current flows from the inside of the exponential gradient line to the edge of the patch, resulting in energy discontinuity, increased antenna loss, reduced gain, and poor radiation performance, making it difficult to meet practical application requirements. Summary of the Invention

[0005] To address the problems existing in the prior art, the present invention provides an antenna array support and its control method.

[0006] This invention is implemented as follows: an antenna array support, comprising: A 64-channel antenna array, consisting of one transmitting antenna and multiple receiving antennas; Antenna array bracket for supporting the 64-channel antenna array.

[0007] Furthermore, the 64-channel antenna array is connected to the 64-channel signal transmitting and receiving device via radio frequency cables and is fixed in a predetermined position by the antenna array bracket.

[0008] Furthermore, the antenna is a Vivaldi antenna with a topology, comprising a single-layer dielectric substrate, a microstrip feed line and an upper radiating patch located on the upper surface of the single-layer dielectric substrate, and a feed balun and a lower radiating patch located on the lower surface of the single-layer dielectric substrate; the upper radiating patch and the lower radiating patch are distributed on the upper and lower surfaces of the single-layer dielectric substrate in a topology structure and are rotationally symmetrical about the electromagnetic radiation direction.

[0009] Furthermore, the edge of a single patch of the radiation patch is surrounded by an outer index line, an inner index line, and an arc line; The microstrip feed line is connected to the lower end of the upper radiating patch, and the other end is connected to the RF connector probe to feed the antenna. The feed balun is formed by two back-to-back elliptical grooves and a rectangular boundary, and is connected to the lower end of the lower radiating patch. The upper and lower radiating patches are bounded by curves that gradually expand from an exponential function, and the lower boundary is bounded by an elliptical arc extending outward from the starting point of the exponential function curve. The opening area that gradually expands between the inner sides of the upper and lower radiating patches is the electromagnetic wave radiation area. The gradient groove line inside the upper boundary satisfies the following: with the intersection of the microstrip feed line and the lower end of the upper radiating patch as the origin, the x-axis is the non-radiating direction and the +y-axis is the radiating direction; the lower boundary is formed by a quarter-elliptical arc curving upwards. The single-layer dielectric substrate is made of FR4 material, with a relative permittivity of 4.4 and a loss tangent of 0.02. FR4 is a common antenna material, which is a glass fiber reinforced epoxy resin material. Compared with other antenna materials, FR4 material usually has a lower permittivity and dielectric loss. In addition, it also has high mechanical strength and adhesion, which makes it advantageous in the fabrication of small microstrip antennas.

[0010] Another object of the present invention is to provide an antenna array support control method using the aforementioned antenna array support, comprising the following steps: 1) Provides a 64-channel antenna array, with one antenna used for transmitting and the remaining multiple antennas used for receiving; 2) Install the antenna array bracket and fix the 64-channel antenna array onto the bracket; 3) Connect the 64-channel signal transmitting and receiving device, including a single-channel transmitting module, a multi-channel receiving module and a clock module, and connect the device to the server via a network cable; 4) Power the server and the 64-channel signal transmitting and receiving device; 5) Transmit detection signals and receive signals reflected by multiple antennas; 6) Transmit the received signals to the server and perform data storage and processing to obtain detection information related to the tunnel walls.

[0011] Furthermore, the 64-channel antenna array is connected to the single-channel transmitting module and the multi-channel receiving module via radio frequency cables, and its position can be adjusted on the antenna array bracket to achieve coverage of a designated area of ​​the tunnel wall.

[0012] Furthermore, the clock module provides a synchronous clock signal to the single-channel transmitting module and the multi-channel receiving module, so that the transmitted signal and the received signal are acquired and recorded under the same time reference.

[0013] Furthermore, the server receives signal data output from the multi-channel receiving module via a network cable, and performs storage and data processing operations in the server to form detection results of the tunnel wall.

[0014] Another object of the present invention is to provide a computer device including a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the antenna array support control method described above.

[0015] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of the antenna array support control method.

[0016] Based on the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solution to be protected by this invention are as follows: The 64-channel antenna array and multi-channel signal transmitting and receiving device proposed in this invention operate synchronously, utilizing single-channel transmission and multi-channel parallel reception to achieve real-time acquisition and multi-dimensional analysis of reflected signals from tunnel walls. A clock module provides a unified clock reference for each channel, significantly reducing phase shift and synchronization errors during signal sampling. Simultaneously, the antenna array bracket allows for flexible fixing and adjustment of the array layout to cover different areas of the tunnel wall, thereby improving the detection accuracy and efficiency of various types of hidden defects.

[0017] Compared to existing technologies, the present invention achieves significant improvements in data acquisition speed, signal synchronization accuracy, and detection range. Multi-channel parallel reception reduces measurement time and improves anti-interference capabilities; a unified clock reference ensures accurate acquisition of high-resolution signals; and a movable or adjustable antenna array support makes the system more adaptable to the diverse tunnel environments. Therefore, the present invention demonstrates higher reliability and practical value in the early identification, quantitative analysis, and subsequent maintenance of hidden damage to tunnel walls.

[0018] This invention has promising applications, designing a non-destructive testing system for hidden damage in tunnel walls that utilizes the propagation characteristics of microwaves in materials. When microwave signals encounter different media or the internal structure of an object, they produce effects such as reflection, transmission, and scattering. By receiving and analyzing these signals, it is possible to determine whether the internal structure of the object has been damaged or is abnormal.

[0019] The antenna of this invention has multiple rectangular slots etched at the edges of the upper and lower radiating patches to reduce current backflow, thereby reducing current backflow on the patch surface and concentrating energy. The antenna of this invention has a simple structure, reasonable dimensions, and effectively improves the antenna's return loss, gain, radiation efficiency, and directivity. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall appearance of the antenna array bracket provided in an embodiment of the present invention; Figure 2 This is an overall anatomical diagram of the antenna array support provided in an embodiment of the present invention; Figure 3 This is a top view of the antenna array support provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the overall antenna structure provided in an embodiment of the present invention; Figure 5 This is a schematic diagram of the front structure of the antenna provided in an embodiment of the present invention; Figure 6 This is a schematic diagram of the antenna rear structure provided in an embodiment of the present invention; Figure 7 This is a simulation-obtained antenna S-parameter curve provided in an embodiment of the present invention; Figure 8 This is a simulation-obtained gain curve diagram provided in the embodiments of the present invention; Figure 9 This is the antenna E-plane radiation pattern at a frequency of 0.5 GHz provided in an embodiment of the present invention; Figure 10 This is the antenna H-plane radiation pattern at a frequency of 0.5 GHz provided in an embodiment of the present invention; Figure 11 This is the antenna E-plane radiation pattern at a frequency of 1 GHz provided in an embodiment of the present invention; Figure 12 This is the antenna H-plane radiation pattern at a frequency of 1 GHz provided in an embodiment of the present invention; Figure 13 This is the antenna E-plane radiation pattern at a frequency of 1.5 GHz provided in an embodiment of the present invention; Figure 14 This is the antenna H-plane radiation pattern at a frequency of 1.5 GHz provided in an embodiment of the present invention; Figure 15 This is the antenna E-plane radiation pattern at a frequency of 2GHz provided in this embodiment of the invention; Figure 16 This is the antenna H-plane radiation pattern at a frequency of 2GHz provided in this embodiment of the invention; In the diagram: 1. One-channel transmitting antenna unit; 2. Sixty-three-channel receiving antenna unit; 3. Sixty-four-channel antenna array; 4. Antenna array support. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] like Figure 1 , Figure 2 , Figure 3 As shown, the 64-channel antenna array 3 is supported by the antenna array bracket 4, and the support connection is installed using screw holes.

[0023] One transmit antenna unit 1 and 63 receive antenna units 2 are fixed on a 64-channel antenna array panel.

[0024] One transmit antenna unit 1 and one transmit module are connected via an RF cable with an SMA connector. Similarly, 63 receive antenna units 2 and 63 receive modules are connected via an RF cable with an SMA connector.

[0025] The 63-channel receiver module, 1-channel transmitter module, and clock module are integrated inside the 64-channel signal transmitter and receiver device and are mounted on the housing of the 64-channel signal transmitter and receiver device using screw holes. The 63-channel receiver module, 1-channel transmitter module, and clock module are connected via RF cables.

[0026] The server and the 64-channel signal transmitter and receiver are connected via network cable with an RJ45 connector.

[0027] The power supply and the 64-channel signal transmitting and receiving device are connected via a power cord. The power supply and the server are connected via a power cord.

[0028] The 64-channel signal transmitter and receiver, along with the server and power supply, are stacked in the rack and secured with screws.

[0029] This embodiment uses a 64-channel antenna array 3 as the main detection component. One transmitting antenna unit 1 and 63 receiving antenna units 2 are both fixed to the antenna array panel and supported by an antenna array bracket 4. The bracket and antenna array are installed using screw holes, facilitating secure positioning and appropriate adjustments during installation and maintenance. This layout allows for a unified arrangement of transmitting and receiving antennas, thus providing a stable radio frequency environment and spatial coverage during subsequent detection.

[0030] The 64-channel signal transmitter and receiver integrates a 1-channel transmitter module, a 63-channel receiver module, and a clock module. All modules are connected via RF cables and SMA interfaces. By positioning and installing them within the same enclosure, the length of external wiring between different modules is reduced, signal loss and interference in the RF link are decreased, and a compact and reliable hardware platform is provided for subsequent system synchronization and data transmission.

[0031] One transmit antenna unit 1 is connected to the one-channel transmit module via an SMA interface RF cable, while the 63-channel receive antenna unit 2 is connected to the 63-channel receive module respectively. This "one transmit, multiple receive" design allows the system to simultaneously acquire reflected signals from different receive antennas, forming a multi-channel parallel acquisition mode. The clock synchronization required by the system is provided by the clock module to both the transmit and receive modules, transmitting a unified time base through RF cables to ensure the consistency of multi-channel signal sampling.

[0032] The server is connected to the 64-channel signal transmitting and receiving device via a standard RJ45 network cable. In this embodiment, the server is responsible not only for providing transmission commands to the transmitting module but also for storing and managing the output signal data from the receiving module. Through Ethernet communication, the server can receive multiple antenna signals with high bandwidth and stability, and perform further data analysis and processing.

[0033] The power supply provides power to both the 64-channel signal transmitter and receiver and the server, connected via power cables. Inside the rack, the power supply, servers, and 64-channel signal transmitter and receiver are centrally located using a stacking and screw-fixed configuration. This layout saves space and facilitates heat dissipation and cabling, making the entire system more maintainable and reliable.

[0034] When the system is put into use, the server communicates with the transmitting module via Ethernet and controls the transmitting antenna to send detection signals towards the target tunnel wall. Any defects or discontinuities inside the wall will reflect or scatter these signals, and the 63-channel receiving antenna unit 2 and the 63-channel receiving module collect these returned signals in parallel. The clock module is responsible for a unified time reference, ensuring that multi-channel data is sampled at the same time. Subsequently, the server reads the collected radio frequency data from the receiving module 5 and processes it. By analyzing the amplitude, phase, and delay information of the signal, the location and extent of hidden damage to the tunnel wall can be located or determined, thereby achieving rapid detection of tunnel structural safety.

[0035] In the method of this invention, a 64-channel antenna array is first required, where a single-channel antenna is used to transmit detection signals, and the remaining multiple antennas are used to receive reflected signals in parallel. By mounting the antenna array on an adjustable antenna array bracket, the antenna position and angle can be flexibly changed according to the specific conditions of the tunnel wall, thereby covering the designated detection area. The antennas are connected to the single-channel transmitting module and the multi-channel receiving module respectively via radio frequency cables, laying the foundation for accurate transmission and synchronous reception of subsequent signals.

[0036] To ensure that the phase and time reference of the signals received by the multiple antennas are consistent, this invention introduces a clock module, which provides a synchronization clock signal to both the single-channel transmitting module and the multi-channel receiving module via RF cables. When the transmitting module sends a probe pulse to one antenna in the antenna array, all receiving antennas complete signal sampling under the same time reference. This significantly reduces the time delay and phase shift in signal acquisition, thereby obtaining more accurate and stable data for detecting subtle defects.

[0037] After the detection signal is transmitted from a single-channel transmitting antenna to the tunnel wall, if there are micro-cracks, voids, or other hidden defects inside the wall, some of the signal will be reflected or scattered at the defect location. Multiple receiving antennas simultaneously pick up these reflected signals, which are then initially amplified and processed in a multi-channel receiving module. Subsequently, the received digitized data is transmitted to a server via network cable. The server not only stores the original received signal but also executes real-time or offline data analysis algorithms to extract information related to tunnel wall defects.

[0038] After receiving reflected signals from multiple antennas, the server uses storage and data processing modules to perform noise reduction, filtering, and time delay compensation on these signals. Using a pre-established tunnel wall structure model or algorithm, the system can further interpret the reflection intensity, arrival time, and phase distribution, thereby identifying potential hidden damage locations in 3D or 2D imaging. This process not only improves the ability to identify hidden dangers such as micro-cracks or cavities but also provides accurate data support for tunnel maintenance and reinforcement decisions.

[0039] An application embodiment of the present invention provides a computer device, which includes a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, the processor performs the steps of the antenna array support control method.

[0040] An application embodiment of the present invention provides a computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the steps of an antenna array support control method.

[0041] like Figure 4-6 The Vivaldi antenna shown includes a single-layer dielectric substrate. A microstrip feed line, an upper radiating patch, and an upper metal patch are sequentially connected to the upper surface of the substrate. A feed balun, a lower radiating patch, and a lower metal patch are sequentially connected to the lower surface of the substrate. The upper and lower radiating patches are distributed in an antipodal structure on the upper and lower surfaces of the substrate 1, and are rotationally symmetrical about the y-axis of the radiation direction. One end of the microstrip feed line is connected to the lower end of the upper radiating patch, and the other end is connected to a 50Ω RF connector probe to feed the antenna. The microstrip line has dimensions of [dimension value missing]. The feed balun 3 is formed by two back-to-back elliptical slots and a rectangular boundary, and is connected to the lower end of the lower radiating patch. Seven equally spaced rectangular slots are evenly distributed in the middle, with slot dimensions of [dimension value missing]. The overall dimensions of the comb structure are [dimension value missing], and these slots are printed on the boundaries of the upper and lower surfaces of the substrate.

[0042] The upper boundaries of the upper and lower radiating patches 402 are enclosed by curves that gradually expand outward from an exponential function, while the lower boundaries are enclosed by elliptical arcs extending outward from the starting point of the exponential function curve. The gradually expanding opening region between the inner sides of the upper boundaries of the upper and lower radiating patches is the electromagnetic wave radiation region. The exponential function curve of the upper boundary satisfies the following equation: with the intersection of the microstrip feed line 2 and the single-layer dielectric substrate as the origin, y is the non-radiative direction, and +y is the radiative direction; the lower boundary is a quarter-elliptical arc with major and minor axes equally divided by y and y respectively, curving upward. The single-layer dielectric substrate 1 uses FR4 material with a relative permittivity of 4.4 and a loss tangent of 0.02.

[0043] The active return loss at the port of the plantar Vivaldi ultrawideband antenna described above was simulated and calculated using the simulation software ANSYS HFSS. The results are as follows: Figure 7 As shown.

[0044] The antenna gain in the above embodiment was simulated and calculated using the simulation software ANSYS HFSS. The results are as follows: Figure 8 The figure shows how the antenna peak gain changes with frequency.

[0045] Figure 9The antenna E-plane radiation pattern of the embodiment of the present invention is shown when operating at 0.5 GHz; the curve is generally trilobed, with the main lobe pointing to the 0° direction and the side lobes being well suppressed, indicating that the frequency point has strong directivity and low cross-polarization within the radiation plane.

[0046] Figure 10 The antenna H-plane radiation pattern at the same frequency of 0.5 GHz is given; it can be seen that the main lobe width is significantly larger than that of the E-plane, the main radiated energy is concentrated in the range of 0° to 90°, the back radiation is effectively suppressed, and a wider azimuth coverage is provided for close-range low-frequency detection.

[0047] Figure 11 The corresponding antenna E-plane pattern of this invention is at 1 GHz; as the frequency increases, the sharpness of the main lobe increases, the pattern exhibits a four-leaf flower shape, the main lobe gain increases and the beam shrinks, demonstrating the high directivity advantage of the Vivaldi structure in the mid-frequency band.

[0048] Figure 12 The antenna H-plane radiation pattern at 1 GHz is shown; the curve consists of three lobes, with the main lobe radiating forward and the side lobe amplitude further reduced. Compared with the H-plane at 0.5 GHz, the beam convergence is better and the symmetry is better, which is beneficial to improving the overall surface scanning accuracy of the array.

[0049] Figure 13 and Figure 14 The E-plane and H-plane radiation patterns at 1.5 GHz are given respectively. At this time, the radiation pattern is a multi-lobed combination. The main lobe maintains high gain output, and the number of side lobes increases but the amplitude is controlled below -10 dB, indicating that the antenna still maintains good radiation consistency after it is above the midpoint of the operating bandwidth.

[0050] Figure 15 and Figure 16 Corresponding to the E-plane and H-plane radiation patterns at 2 GHz; the main lobes of both patterns are significantly narrowed, the pointing accuracy is the highest, the overall radiation pattern tends to be a five-lobed structure, and the side-back radiation is further suppressed, providing higher angular resolution and signal purity for high-speed imaging or deep penetration detection.

[0051] It should be noted that embodiments of the present invention can be implemented in hardware, software, or a combination of both. The hardware portion can be implemented using dedicated logic; the software portion can be stored in memory and executed by a suitable instruction execution system, such as a microprocessor or dedicated-design hardware. Those skilled in the art will understand that the above-described devices and methods can be implemented using computer-executable instructions and / or included in processor control code, for example, such code provided on a carrier medium such as a disk, CD, or DVD-ROM, a programmable memory such as read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. The devices and modules of the present invention can be implemented by hardware circuitry such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, or programmable hardware devices such as field-programmable gate arrays, programmable logic devices, etc., or by software executed by various types of processors, or by a combination of the above-described hardware circuitry and software, such as firmware.

[0052] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An antenna array support, characterized in that, include: Rigid base; A pitch adjustment mechanism is mounted on the base; A planar mounting plate is connected to the base via the pitch adjustment mechanism. The planar mounting plate is provided with a positioning hole array for fixing the 64-channel Vivaldi antenna array. A cable channel runs through the base and the pitch adjustment mechanism, the cable channel being used to accommodate and shield the radio frequency cables of the 64-channel antenna array.

2. The antenna array bracket as described in claim 1, characterized in that, The pitch adjustment mechanism is a double universal joint mechanism with the first and second rotating shafts orthogonally arranged, used to continuously adjust and lock the attitude of the planar mounting plate in the pitch and roll directions.

3. The antenna array support as described in claim 1, characterized in that, An azimuth rotation platform is provided between the base and the pitch adjustment mechanism. The azimuth rotation platform includes an angle encoder for outputting the azimuth angle information of the planar mounting plate.

4. The antenna array bracket as described in claim 1, characterized in that, The base is equipped with a forced air cooling channel, which is distributed along the outer wall of the cable channel to reduce the operating temperature rise of the radio frequency cable.

5. A 64-channel radar antenna device, characterized in that, include: The antenna array support as described in any one of claims 1-4; The 64-channel Vivaldi antenna array has one channel for transmitting and the remaining channels for receiving. Radio frequency cable bundle, used to connect the antenna array to the 64-channel transceiver; The attitude measurement module is used to acquire the spatial attitude information of the antenna array support in real time.

6. An antenna array control method, characterized in that, Includes the following steps: a) Fix a 64-channel antenna array on an antenna array bracket, with one antenna used for transmitting and the rest used for receiving; b) Connect the single-channel transmitter module, the multi-channel receiver module, and the clock module to the antenna array via radio frequency cables; c) Connect the multi-channel receiving module to the server via a network cable and power the device. d) The transmitting module transmits a detection signal, and the receiving module receives the reflected signal under the same clock reference; e) The received signal is transmitted to the server, which stores and processes the received signal to obtain detection information related to the structure under test.

7. The antenna array control method as described in claim 6, characterized in that, Before step a), the method further includes: adjusting the azimuth, elevation, and roll angles of the antenna array support so that the main coverage area of ​​the 64-channel antenna array coincides with the target detection area.

8. A computer device comprising a processor and a memory, the memory storing a computer program that, when executed by the processor, causes the processor to perform the antenna array control method of claim 6 or 7.

9. A computer-readable storage medium storing a computer program, which, when executed by a processor, causes the processor to perform the antenna array control method of claim 6 or 7.

10. The 64-channel radar antenna device as described in claim 5, characterized in that, Each pair of Vivaldi antennas includes: a single-layer dielectric substrate, a microstrip feed line and an upper radiating patch located on the upper surface of the dielectric substrate, and a feed balun and a lower radiating patch located on the lower surface of the dielectric substrate, wherein the upper radiating patch and the lower radiating patch are topologically symmetrical about the electromagnetic radiation axis.

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