An adjustable fresnel zone blocking anechoic chamber structure and testing method for antenna near-field testing

Abstract

The embodiment of the application provides a tunable Fresnel region blocking darkroom structure and a test method for antenna near-field test, relates to the technical field of electromagnetic compatibility and antenna measurement, and the structure comprises a darkroom main body cavity, a to-be-tested antenna mounting platform, a scanning component and a tunable Fresnel region blocking component; the to-be-tested antenna mounting platform is arranged at the bottom center of the darkroom main body cavity and is used for carrying the to-be-tested antenna; the scanning component is arranged at the top center of the darkroom main body cavity and is used for radiating / receiving signals downward along a vertical axis; the tunable Fresnel region blocking component is horizontally arranged between the to-be-tested antenna mounting platform and the scanning component and can be adjusted in position along the vertical direction. The darkroom structure provided by the application has the advantages of compact structure, flexible function and strong adaptability.

Description

Technical Field

[0001] This application relates to the fields of electromagnetic compatibility and antenna measurement technology, and more specifically, to an adjustable Fresnel zone anechoic chamber structure and testing method for near-field antenna testing. Background Technology

[0002] In near-field antenna testing, the antenna under test (AUT) is typically placed in a shielded room covered with absorbing material. The near-field distribution is scanned by a probe, and the far-field radiation pattern is inverted. However, in a traditional rectangular anechoic chamber, due to limited space, the Fresnel zone of the antenna radiation is easily affected by reflected waves from the side walls and top and bottom surfaces, leading to increased measurement errors, especially in low-frequency bands or when testing large-aperture antennas.

[0003] While existing technologies employ conical absorbers or tilted wall designs to reduce reflections, they cannot specifically block Fresnel zone propagation paths on specific routes. Other solutions introduce metal baffles or absorbing curtains, but their fixed positions make them unsuitable for testing antennas of different frequencies and sizes, lacking flexibility and versatility. Therefore, a novel structural design is urgently needed that can dynamically adjust to the testing scenario, effectively isolate Fresnel zone interference, and maintain the overall stability of the anechoic chamber's performance. Summary of the Invention

[0004] The embodiments of this application provide an adjustable Fresnel zone anechoic chamber structure and testing method for near-field antenna testing, in order to solve the technical problems existing in the prior art.

[0005] Other features and advantages of this application will become apparent from the following detailed description, or may be learned in part from practice of this application.

[0006] According to a first aspect of the embodiments of this application, an adjustable Fresnel zone blocked anechoic chamber structure for antenna near-field testing is provided, comprising: The main cavity of the anechoic chamber, the mounting platform for the antenna under test, the scanning components, and the adjustable Fresnel zone blocking components; The antenna under test mounting platform is located at the bottom center of the anechoic chamber's main cavity and is used to support the antenna under test; The scanning component is located at the top center of the main cavity of the darkroom and is used to radiate / receive signals downward along the vertical axis. The adjustable Fresnel zone blocking component is horizontally positioned between the antenna under test mounting platform and the scanning component, and its position can be adjusted in the vertical direction.

[0007] In some embodiments of this application, based on the foregoing scheme, the adjustable Fresnel zone barrier is detachably mounted on the two side walls of the main cavity of the darkroom.

[0008] In some embodiments of this application, based on the foregoing scheme, guide mechanisms are respectively installed on the two side walls of the main cavity of the darkroom; The adjustable Fresnel zone barrier component has two ends connected to guide mechanisms on both sides of the wall, and its vertical position can be adjusted through the guide mechanisms on both sides.

[0009] In some embodiments of this application, based on the foregoing scheme, the guide mechanism is equipped with a position feedback sensor.

[0010] In some embodiments of this application, based on the foregoing scheme, the guiding mechanism is selected from any one of electric slide rails, hydraulic cylinders, gear racks or magnetic levitation systems.

[0011] In some embodiments of this application, based on the foregoing scheme, the surface of the adjustable Fresnel zone blocking component is coated with a broadband absorbing material or a composite impedance matching layer.

[0012] In some embodiments of this application, based on the foregoing scheme, an intelligent control system is also included. The intelligent control system automatically calculates the optimal blocking position based on the input antenna parameters and controls the guide mechanism to drive the adjustable Fresnel blocking component to the optimal blocking position.

[0013] In some embodiments of this application, based on the aforementioned scheme, auxiliary positioning marker components are provided at the four corners of the main cavity of the anechoic chamber to assist the user in accurately calibrating the adjustable Fresnel zone blocking component to coincide with the vertical axis.

[0014] In some embodiments of this application, based on the aforementioned scheme, the inner wall of the main cavity of the anechoic chamber is entirely covered with pyramid-shaped or wedge-shaped absorbing material, and all joints are electromagnetically sealed.

[0015] According to a second aspect of the embodiments of this application, an antenna near-field testing method based on the anechoic chamber structure described in the first aspect is provided, comprising the steps of: a) Install the antenna under test onto the bottom platform; b) Determine the theoretical Fresnel zone boundary based on the antenna's operating frequency and aperture; c) Adjust the adjustable Fresnel zone blocking component to the specified height so that it precisely cuts off the path of the strongest reflection; d) Start the scanning procedure to acquire near-field data; e) Reconstruct the far-field radiation pattern using the algorithm and evaluate the magnitude of the error improvement.

[0016] The technical solution of this application has the following beneficial effects: 1. Precisely suppress Fresnel zone interference: By physically blocking the main reflection path, the primary / secondary reflected waves from side walls or other locations are significantly reduced, improving the signal-to-noise ratio; 2. High flexibility: It can automatically optimize the blocking height according to the antenna operating frequency, aperture size, and test distance to avoid excessive blocking of the main lobe energy; 3. Multifunctional expansion capability: In addition to basic barrier, it can also be used as a "virtual ground" or "reference plane"; 4. Easy to maintain and upgrade: The modular design allows for the replacement of damaged parts individually without affecting the operation of the entire machine; 5. Strong compatibility: Applicable to various near-field scanning systems, compact field pre-verification, OTA testing and other application scenarios.

[0017] 6. Supports scenarios such as mass production.

[0018] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings: Figure 1 A schematic diagram of an adjustable Fresnel zone anechoic chamber structure for near-field antenna testing according to an embodiment of this application is shown.

[0020] Explanation of reference numerals in the attached figures 1-Anechoic chamber main body, 2-Scanning assembly, 3-Antenna under test mounting platform, 4-Adjustable Fresnel zone blocking assembly, 5-Vertical axis, 6-Side fixing bracket. Detailed Implementation

[0021] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided to make this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art.

[0022] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Numerous specific details are provided in the following description to give a thorough understanding of embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, apparatuses, steps, etc., can be employed. In other instances, well-known methods, apparatuses, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0024] The following detailed description of some embodiments of this application will be provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0025] To address the technical problems existing in the prior art, embodiments of this application provide an adjustable Fresnel zone anechoic chamber structure for antenna near-field testing, comprising: The main cavity of the anechoic chamber, the mounting platform for the antenna under test, the scanning components, and the adjustable Fresnel zone blocking components; The antenna under test mounting platform is located at the bottom center of the anechoic chamber's main cavity and is used to support the antenna under test; The scanning component is located at the top center of the main cavity of the darkroom and is used to radiate / receive signals downward along the vertical axis. The adjustable Fresnel zone blocking component is horizontally positioned between the antenna under test mounting platform and the scanning component, and its position can be adjusted in the vertical direction.

[0026] It should be noted that, in this embodiment, the antenna under test mounting platform may be equipped with a lifting mechanism or a conveyor belt mechanism.

[0027] It should be noted that, in this embodiment, the scanning component can be a scanning probe array or a single-point scanning device.

[0028] Understandably, in this embodiment, the adjustable Fresnel zone blocking component interferes with the electromagnetic wave propagation path between the antenna under test and the scanning component by moving it vertically up and down. For example, if the adjustable Fresnel zone blocking component is adjusted upwards, the closer it is to the scanning component, the larger the area of ​​electromagnetic waves radiating downwards between the antenna under test and the scanning component; conversely, if the adjustable Fresnel zone blocking component is adjusted downwards, the closer it is to the antenna under test, the smaller the area of ​​electromagnetic waves radiating downwards between the antenna under test and the scanning component.

[0029] For example, see Figure 1 The diagram shows a schematic structural diagram of an adjustable Fresnel zone anechoic chamber structure for near-field antenna testing according to an embodiment of this application.

[0030] like Figure 1 As shown, the antenna under test mounting platform 3, the scanning component 2, and the adjustable Fresnel zone blocking component 4 are all located inside the anechoic chamber main cavity 1. The scanning component 2 is located at the top center of the anechoic chamber main cavity 1, and the antenna under test mounting platform 3 is located at the bottom center of the anechoic chamber main cavity 1. The antenna under test on the antenna under test mounting platform 3 is aligned with the scanning component 2 along the vertical axis 5. The adjustable Fresnel zone blocking component 4 is located between the antenna under test mounting platform 3 and the scanning component 2. The adjustable Fresnel zone blocking component 4 has a gap in the middle, through which electromagnetic waves propagate between the antenna under test and the scanning component. The adjustable Fresnel zone blocking component 4 can move vertically within the anechoic chamber main cavity 1. When the adjustable Fresnel zone blocking component 4 moves, the electromagnetic wave radiation area will increase or decrease due to the change in the position of the gap, thereby achieving blocking adjustment.

[0031] In some feasible embodiments, based on the aforementioned scheme, the adjustable Fresnel zone barrier is detachably mounted on the two side walls of the main cavity of the anechoic chamber.

[0032] For example, such as Figure 1 As shown, the adjustable Fresnel zone blocking component is detachably mounted on the two side walls of the main cavity 1 of the anechoic chamber via side fixing brackets 6. Furthermore, the adjustable Fresnel zone blocking component supports quick assembly and disassembly modular management, meaning that the adjustable Fresnel zone blocking component adopts a modular design and supports quick replacement of sub-modules with different frequency responses, polarization characteristics, or dimensions.

[0033] In some feasible embodiments, based on the aforementioned scheme, guide mechanisms are respectively installed on the two side walls of the main cavity of the darkroom; The adjustable Fresnel zone barrier component has two ends connected to guide mechanisms on both sides of the wall, and its vertical position can be adjusted through the guide mechanisms on both sides.

[0034] It is understood that in this embodiment, the guide mechanisms on both sides are vertically arranged along the two side walls of the main cavity of the darkroom to ensure that the adjustable Fresnel zone blocking assembly can be adjusted in the vertical direction.

[0035] In some feasible embodiments, based on the foregoing scheme, the guide mechanism is equipped with a position feedback sensor.

[0036] Understandably, position feedback sensors can acquire position information in real time, allowing staff to adjust their positions accordingly.

[0037] In some feasible embodiments, based on the foregoing scheme, the guiding mechanism is selected from any one of electric slide rails, hydraulic cylinders, gear racks or magnetic levitation systems.

[0038] In some feasible embodiments, based on the foregoing scheme, the surface of the adjustable Fresnel zone blocking component is coated with broadband absorbing material or a composite impedance matching layer.

[0039] In some feasible embodiments, based on the foregoing scheme, an intelligent control system is also included. The intelligent control system automatically calculates the optimal blocking position based on the input antenna parameters and controls the guide mechanism to drive the adjustable Fresnel blocking component to the optimal blocking position.

[0040] It is understood that, in this embodiment, the intelligent control system can be linked with the position feedback sensor.

[0041] In some feasible embodiments, based on the aforementioned scheme, auxiliary positioning marker components are provided at the four corners of the main cavity of the anechoic chamber to assist the user in accurately calibrating the adjustable Fresnel zone blocking component to coincide with the vertical axis.

[0042] In some feasible embodiments, based on the aforementioned scheme, the inner wall of the main cavity of the anechoic chamber is entirely covered with pyramid-shaped or wedge-shaped absorbing material, and all joints are electromagnetically sealed.

[0043] It is understood that in this embodiment, the anechoic chamber main cavity covered with absorbing material forms an electromagnetic shielding environment.

[0044] Based on the same inventive concept, this application also provides an antenna near-field testing method based on the anechoic chamber structure described in any of the above embodiments, including the following steps: a) Install the antenna under test onto the bottom platform; b) Determine the theoretical Fresnel zone boundary based on the antenna's operating frequency and aperture; c) Adjust the adjustable Fresnel zone blocking component to the specified height so that it precisely cuts off the path of the strongest reflection; d) Start the scanning procedure to acquire near-field data; e) Reconstruct the far-field radiation pattern using the algorithm and evaluate the magnitude of the error improvement.

[0045] In summary, this application provides a compact, flexible, and highly adaptable antenna near-field testing anechoic chamber with the following advantages: (1) By adding a transverse Fresnel zone blocking component that can be moved up and down or completely disassembled, active control of the critical interference path is realized.

[0046] (2) Significantly improve measurement accuracy and reduce system uncertainty.

[0047] (3) It also supports switching between multiple test modes.

[0048] (4) It can be extended to the production line for automatic loading and unloading.

[0049] (5) It can significantly reduce production costs.

[0050] Other embodiments of this application will readily conceive of by those skilled in the art upon consideration of the specification and practice of the embodiments disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. It should be understood that this application is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. An adjustable Fresnel zone anechoic chamber structure for near-field antenna testing, characterized in that, include: The main cavity of the anechoic chamber, the mounting platform for the antenna under test, the scanning components, and the adjustable Fresnel zone blocking components; The antenna under test mounting platform is located at the bottom center of the anechoic chamber's main cavity and is used to support the antenna under test; The scanning component is located at the top center of the main cavity of the darkroom and is used to radiate / receive signals downward along the vertical axis. The adjustable Fresnel zone blocking component is horizontally positioned between the antenna under test mounting platform and the scanning component, and its position can be adjusted in the vertical direction.

2. The anechoic chamber structure according to claim 1, characterized in that, The adjustable Fresnel zone barrier is detachably mounted on both sides of the main cavity of the darkroom.

3. The anechoic chamber structure according to claim 2, characterized in that, Guide mechanisms are installed on both sides of the main cavity of the darkroom; The adjustable Fresnel zone barrier component has two ends connected to guide mechanisms on both sides of the wall, and its vertical position can be adjusted through the guide mechanisms on both sides.

4. The anechoic chamber structure according to claim 3, characterized in that, The guide mechanism is equipped with a position feedback sensor.

5. The anechoic chamber structure according to claim 3, characterized in that, The guiding mechanism can be any one of an electric slide rail, a hydraulic cylinder, a gear rack and pinion system, or a magnetic levitation system.

6. The anechoic chamber structure according to any one of claims 1-5, characterized in that, The surface of the adjustable Fresnel zone blocking component is covered with broadband absorbing material or a composite impedance matching layer.

7. The anechoic chamber structure according to any one of claims 1-5, characterized in that, It also includes an intelligent control system, which automatically calculates the optimal blocking position based on the input antenna parameters and controls the guide mechanism to drive the adjustable Fresnel blocking component to the optimal blocking position.

8. The anechoic chamber structure according to claim 1, characterized in that, The four corners of the main cavity of the anechoic chamber are equipped with auxiliary positioning marker components to help users accurately calibrate the adjustable Fresnel zone barrier component to coincide with the vertical axis.

9. The anechoic chamber structure according to claim 1, characterized in that, The inner walls of the main cavity of the anechoic chamber are entirely covered with pyramid-shaped or wedge-shaped absorbing materials, and all joints are electromagnetically sealed.

10. A method for near-field testing of an antenna based on the anechoic chamber structure described in any one of claims 1-9, characterized in that, Including the following steps: a) Install the antenna under test onto the bottom platform; b) Determine the theoretical Fresnel zone boundary based on the antenna's operating frequency and aperture; c) Adjust the adjustable Fresnel zone blocking component to the specified height so that it precisely cuts off the path of the strongest reflection; d) Start the scanning procedure to acquire near-field data; e) Reconstruct the far-field radiation pattern using the algorithm and evaluate the magnitude of the error improvement.

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