A foldable reconfigurable stirrer for a reverberation chamber

Abstract

The application discloses a kind of folding reconfigurable stirrers for reverberation chamber, it includes folding hypersurface (1), guide rail motor (2), guide rail (3), mobile long rod (4) and bottom plate (5);Folding subarray (11) includes m*n folding units (10), there is phase gradient between each row and each column folding unit (10);Guide rail motor (2) is using guide rail (3) can be hauled mobile long rod (4) along guide rail (3) to and fro movement, make folding hypersurface (1) be in extension or folding state;Change the folding angle of folding hypersurface (1) can control the reflection and refraction deflection angle of electromagnetic wave;The application realizes the stirring of electromagnetic wave in reverberation chamber, with the characteristics of small occupied volume, thin structure, reduces the cavity space occupied by stirrer, increases the equivalent working space of reverberation chamber;With more tunable mode than electrically tunable reconfigurable hypersurface stirrer, the comprehensive cost is lower.

Description

Technical Field

[0001] This invention relates to a novel folded metasurface structure stirrer for reverberation chambers, belonging to the field of metasurface reverberation chambers. Background Technology

[0002] With the development of wireless communication technology, various wireless devices have brought great convenience to life, but also created a rapidly growing demand for reliable, efficient, and repeatable over-the-air (OTA) testing. A reverberation chamber provides a high-field-strength, statistically uniform, and isotropic electromagnetic testing environment, suitable for electromagnetic compatibility (EMC) testing of electronic equipment, reducing testing costs and improving testing efficiency. A stirrer is a crucial component of the reverberation chamber, used for stirring the electromagnetic field within the chamber. Currently, most reverberation chambers use metal mechanical stirrers; the larger the stirrer, the better the reverberation chamber performance. However, while large-volume mechanical stirrers improve stirring performance, they also increase construction costs and drastically reduce the working space within the reverberation chamber. Metasurfaces are surface materials whose electromagnetic beam direction and amplitude can be controlled. Reconfigurable metasurfaces can provide different stirring samples within the reverberation chamber, improving performance while occupying almost no of the original working space. Summary of the Invention

[0003] To address the issues of large volume, complex electrically tunable metasurface structure, relatively few controllable states, and high processing costs associated with traditional reverberation chamber metal mechanical stirrers, this invention proposes a foldable reconfigurable stirrer for reverberation chambers. This stirrer offers more controllable states, a simpler structure, and lower costs compared to electrically tunable reconfigurable metasurfaces.

[0004] The technical solution of this invention is: A foldable reconfigurable stirrer for a reverberation chamber includes a foldable metasurface, a guide rail motor, a guide rail, a moving rod, and a base plate. The foldable metasurface includes a foldable subarray, a moving side plate, and a fixed side plate. The foldable subarray includes m*n folding units. The foldable metasurface is located on top of the base plate. The moving rod is connected to the moving side plate, and the fixed side plate is fixed to the outer edge of the base plate. The guide rail is fixed to the bottom edge of the base plate and perpendicular to the fixed side plate. The guide rail motor can pull the moving rod back and forth along the guide rail to keep the foldable metasurface in an extended or folded state. The moving rod can move in the opposite direction to the outer edge and extend to its maximum extent, at which point the foldable metasurface is in an extended state. When the moving rod is not in an extended state, the foldable metasurface is in a folded state. The closer the moving rod is to the outer edge, the higher the degree of folding of the foldable metasurface. The base plate is transparent to electromagnetic waves, and the folding units are partially transparent to electromagnetic waves.

[0005] When the folded metasurface is in an extended state, the normals of all folding units point to the normal of the base plate; when the folded metasurface is in a folded state, the normals of some folding units point in one direction, while the normals of other folding units point in another direction, and the directions of the two normals are different; by changing the degree of folding of the folded metasurface, the normals and folding angles of each folding unit also change, so that the folded metasurface can produce a variety of different distributions of reflection phases, and at the same time produce a variety of different distributions of transmission phases.

[0006] The folding unit includes an inner metal ring, an outer metal ring, and a dielectric substrate. One side of the dielectric substrate has an inner metal ring and an outer metal ring, both of which are square and lie on the same plane. The inner metal ring is located inside the outer metal ring and is connected by two metal connecting strips. This ensures that the reflection phase of the folding unit is related to the incident angle of the incident wave, and also that the transmission phase of the folding unit is related to the incident angle of the incident wave. The larger the incident angle of the incident wave, the smaller the reflection phase and the smaller the transmission phase of the folding unit. Each folding unit has an equivalent polarization axis located in the plane containing the inner and outer metal rings. When the angle between the polarization of the incident wave and the polarization axis changes, the relative magnitudes of the reflected and transmitted wave amplitudes, the reflection phase, and the transmission phase all change. Adjusting the polarization axis angle of the folding unit allows for the control of the reflection and transmission phases generated by the folding unit.

[0007] In the aforementioned folded subarray, each row of m folded units forms a one-dimensional row array, and the entire folded subarray has n one-dimensional row arrays; in the folded subarray, each column of n folded units forms a one-dimensional column array, and the entire folded subarray has m one-dimensional column arrays; in each one-dimensional row array, the polarization axes of adjacent folded units are staggered, and a metal-free dielectric layer fold line is left between adjacent folded units. When the folded metasurface is in an extended state, there is a 360° / m phase gradient between adjacent folded units for reflection and transmission; in each one-dimensional column array, the polarization axes of adjacent folded units are staggered, and a metal-free dielectric layer fold line is left between adjacent folded units. When the folded metasurface is in an extended state, there is a 360° / n phase gradient between adjacent folded units for reflection and transmission; the reflected beam can generate a beam deflection angle along the direction of both rows and columns of the folded subarray.

[0008] The guide rail maintains a certain distance from the folded metasurface to avoid friction with the folded metasurface.

[0009] Folded units generate both reflected and transmitted waves, thus folded metasurfaces can disperse incident beams into multiple transmitted and reflected beams.

[0010] The base plate is made of a material that can transmit electromagnetic waves, such as a dielectric substrate, plastic, or rigid cardboard.

[0011] The base plate has a certain degree of rigidity to support the folded metasurface and ensure that the folded metasurface remains stable during the folding process.

[0012] Changing the position of the moving rod alters the degree and angle of folding of the folded metasurface, enabling the continuous generation of reflected and transmitted beams with different deflection angles, thereby stirring the field within the reverberation chamber.

[0013] By using the motor port on the wall of the reverberation chamber and controlling the guide rail motor with the drive motor outside the reverberation chamber, the foldable reconfigurable stirrer for the reverberation chamber can achieve automatic mechanical stirring of the reverberation chamber.

[0014] The beneficial effects of this invention are as follows: This invention utilizes a folded metasurface to disperse the incident beam into multiple reflected and transmitted beams with deflection angles. By changing the folding angle of the folded metasurface, the normal of the folding unit, and the normal of the polarization axis of the folding unit, the deflection angles of the reflected and transmitted beams can be controlled, thereby achieving continuous stirring of the field inside the reverberation chamber. This invention features a small footprint and thin structure, reducing the cavity space occupied by the folded structure stirrer and increasing the equivalent working space of the reverberation chamber. This invention has more modes than existing metasurfaces, more tunable modes than electrically tunable reconfigurable metasurface structures, and has a simpler structure and lower overall cost. Automatic stretching and compression of the folded metasurface was achieved using a guide rail motor. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of a foldable reconfigurable stirrer for a reverberation chamber provided in an embodiment of the present invention.

[0016] Figure 2 This is a schematic diagram of a folded metasurface of a folded reconfigurable stirrer for a reverberation chamber provided in an embodiment of the present invention.

[0017] Figure 3 This is a schematic diagram of two adjacent folded units when the folded metasurface of a folded reconfigurable stirrer for a reverberation chamber is in a folded state, according to an embodiment of the present invention.

[0018] Figure 4 This is a schematic diagram of the folded metasurface of a foldable reconfigurable stirrer for a reverberation chamber provided in an embodiment of the present invention, when the folded metasurface is in an extended state.

[0019] Figure 5 This is a schematic diagram of a folded subarray of a folded metasurface for a folded reconfigurable stirrer used in a reverberation chamber, provided by an embodiment of the present invention.

[0020] Figure 6 This is a schematic diagram of the structure of a folding unit of a foldable reconfigurable stirrer for a reverberation chamber provided in an embodiment of the present invention.

[0021] Figure 7 This is a schematic diagram of the unit arrangement of a one-dimensional row array of a foldable reconfigurable stirrer for a reverberation chamber provided in an embodiment of the present invention.

[0022] Figure 8 This is a measured curve of the number of independent samples generated when a foldable reconfigurable stirrer for a reverberation chamber is used in a reverberation chamber with dimensions of 0.938 m * 1.166 m * 1.439 m.

[0023] The figure includes: 1 folded metasurface, 10 folded unit, 11 folded subarray, 101 inner metal ring, 102 outer metal ring, 103 dielectric substrate, 104 metal connecting strip, 105 polarization shaft, 2 guide rail motor, 3 guide rail, 4 moving rod, 5 base plate, 51 outer edge, 53 bottom edge, 6 moving side plate, and 7 fixed side plate. Implementation

[0024] The invention will now be further explained with reference to the accompanying drawings.

[0025] As attached Figure 1 To the attached Figure 3 As shown, a foldable reconfigurable stirrer for a reverberation chamber includes a foldable metasurface 1, a guide rail motor 2, a guide rail 3, a moving rod 4, and a base plate 5. The foldable metasurface 1 includes a foldable subarray 11, a moving side plate 6, and a fixed side plate 7. The foldable subarray 11 includes m*n folding units 10. The foldable metasurface 1 is located on top of the base plate 5. The moving rod 4 is connected to the moving side plate 6, and the fixed side plate 7 is fixed to the outer edge 51 of the base plate 5. The guide rail 3 is fixed to the bottom edge 53 of the base plate 5 and is perpendicular to the fixed side plate 7. The machine 2 uses the guide rail 3 to pull the moving rod 4 back and forth along the guide rail 3, so that the folding metasurface 1 is in an extended or folded state; the moving rod 4 can move in the opposite direction to the outer edge 51 and extend to the maximum extent, at which time the folding metasurface 1 is in an extended state; when the moving rod 4 is not in an extended state, the folding metasurface 1 is in a folded state, and the closer the moving rod 4 is to the outer edge 51, the higher the degree of folding of the folding metasurface 1; the base plate 5 can transmit electromagnetic waves, and the folding unit 10 can transmit some electromagnetic waves.

[0026] As attached Figure 4 As shown, when the folded metasurface 1 is in the extended state, the normals of the folding units 10 all point towards the normals of the base plate 5; as shown in the attached diagram. Figure 5As shown, when the folded metasurface 1 is in a folded state, the normal of some folding units 10 points in one direction, while the normal of other folding units 10 points in another direction, and the directions of the two normals are different. By changing the degree of folding of the folded metasurface 1, the normal and folding angle of each folding unit 10 also change, so that the folded metasurface 1 can generate a variety of different distributions of reflection phases, and at the same time generate a variety of different distributions of transmission phases.

[0027] As attached Figure 6 As shown, the folding unit 10 includes an inner metal ring 101, an outer metal ring 102, and a dielectric substrate 103. One side of the dielectric substrate 103 has an inner metal ring 101 and an outer metal ring 102, both of which are square. The inner metal ring 101 and the outer metal ring 102 are on the same plane, with the inner metal ring 101 located inside the outer metal ring 102. The inner metal ring 101 and the outer metal ring 102 are connected by two metal connecting strips 104. This ensures that the reflection phase of the folding unit 10 is related to the incident angle of the incident wave, and also ensures that the transmission phase of the folding unit 10... The phase is related to the incident angle of the incident wave; the larger the incident angle of the incident wave, the smaller the reflection phase of the folding unit 10 and the smaller the transmission phase of the folding unit 10; each folding unit 10 has an equivalent polarization axis 105, which is located in the plane containing the inner metal ring 101 and the outer metal ring 102; when the angle between the polarization of the incident wave and the polarization axis 105 changes, the relative magnitude of the amplitude of the reflected wave and the transmitted wave, as well as the reflection phase and the transmission phase, all change; adjusting the angle of the polarization axis 105 of the folding unit 10 can control the reflection phase and the transmission phase generated by the folding unit 10.

[0028] As attached Figure 2 As shown, in the folded subarray 11, each row of m folded units 10 forms a one-dimensional row array, and the entire folded subarray 11 has n one-dimensional row arrays; in the folded subarray 11, each column of n folded units 10 forms a one-dimensional column array, and the entire folded subarray 11 has m one-dimensional column arrays; as shown in the appendix. Figure 7 As shown, in each one-dimensional row array, the polarization axes 105 of adjacent folded units 10 are staggered, and a metal-free dielectric layer folding line is left between adjacent folded units 10. When the folded metasurface 1 is in an extended state, there is a reflection and transmission phase gradient of 360° / m between adjacent folded units 10. In each one-dimensional column array, the polarization axes 105 of adjacent folded units 10 are staggered, and a metal-free dielectric layer folding line is left between adjacent folded units 10. When the folded metasurface 1 is in an extended state, there is a reflection and transmission phase gradient of 360° / n between adjacent folded units 10. The reflected beam can generate a beam deflection angle along the row and column directions of the folded subarray 11.

[0029] The guide rail 3 maintains a certain distance from the folded metasurface 1 to avoid friction with the folded metasurface 1.

[0030] The folded unit 10 generates both reflected and transmitted waves, so the folded metasurface 1 can disperse the incident beam into multiple transmitted and reflected beams.

[0031] The base plate 5 is made of a material that can transmit electromagnetic waves, such as a dielectric substrate, plastic, or rigid cardboard.

[0032] The base plate 5 has a certain degree of rigidity to support the folded metasurface 1 and ensure that the folded metasurface 1 remains stable during the stretching and folding process.

[0033] Changing the position of the moving rod 4 changes the degree and angle of folding of the folded metasurface 1, which can continuously generate reflected and transmitted beams with different deflection angles, thereby achieving stirring of the field inside the reverberation chamber.

[0034] As attached Figure 2 As shown, in this embodiment, in the folded metasurface 1, each folded subarray 11 consists of 8*8 folded units 10. To expand the effective area, the folded metasurface 1 has four folded subarrays 11, with a total of 16*16 periodically arranged folded units 10. In the extended state, the size of the folded metasurface 1 is 400 mm*400 mm. In each folded subarray 11, 8 folded units 10 in each row constitute a one-dimensional row array of the folded subarray 11, for a total of 8 one-dimensional row arrays; in each row array, the polarization axes 105 of adjacent folded units 10 are staggered, and there is a phase gradient of 45° between adjacent folded units 10, with each row array covering a 360° phase interval. In the folded subarray 11, each column of 8 folded units 10 constitutes a one-dimensional column array of the folded subarray 11, and there are a total of 8 one-dimensional column arrays; in each column array, the polarization axes 105 of adjacent folded units 10 are staggered, and there is a phase gradient of 45° between adjacent folded units 10, and each column array covers a 360° phase interval.

[0035] Along both the row and column directions, the folding unit 10 has its own deflection angle for each reflected beam, and the vector superposition of the two determines the actual deflection angle of the reflected beam; along the row and column directions, the folding unit 10 has its own deflection angle for each transmitted beam, and the vector superposition of the two determines the actual deflection angle of the transmitted beam.

[0036] The folded metasurface 1 can use 0.25 mm thick F4B material as the dielectric substrate, with copper plating on one side. Each folded unit 10 is a square with a side length of 25 mm. By changing the angle of the polarization axis 105 of the folded unit 10, the reflection phase and transmission phase generated by the folded unit 10 can be controlled, so that the reflected wave between adjacent folded units 10 generates a reflection phase gradient, and the transmitted wave between adjacent folded units 10 generates a transmission phase gradient. In the moving direction of the moving rod 4, a 0.2 mm wide metal-free dielectric layer folding line is left between each row of adjacent folded units 10 of the folded metasurface 1. As the folding angle α of the folded unit 10 changes, the equivalent period of the folded unit 10 also changes, and the reflection phase and transmission phase generated by the folded unit 10 change accordingly. Consequently, the deflection angles of the reflected beam and the transmitted beam change, realizing real-time control of the deflection angles of the reflected beam and the transmitted beam by the folded metasurface 1.

[0037] By using the motor port on the wall of the reverberation chamber, the drive motor outside the reverberation chamber controls the guide rail motor 2, and the foldable reconfigurable stirrer for the reverberation chamber can realize the mechanical automatic stirring of the reverberation chamber.

[0038] The application effects of this invention will be further described below with reference to simulation.

[0039] Appendix Figure 8 The present invention is used in a reverberation chamber with dimensions of 0.938 m * 1.166 m * 1.439 m. The measured curves of the number of independent samples generated by the folded metasurface 1 are shown when the distance between the movable side plate 6 and the fixed side plate 7 is changed from 12 cm to 34 cm in an embodiment of the present invention. It can be seen that the number of independent samples generated by the embodiment of the present invention increases with increasing frequency.

[0040] In summary, the foldable reconfigurable stirrer of the reverberation chamber of this invention can continuously slide and stir within the reverberation chamber, generating a large number of independent samples. This technical solution introduces the folded metasurface 1 into the reverberation chamber, increasing the effective working space within the reverberation chamber and optimizing the stirring mode of the metasurface in the reverberation chamber, thus showing good application prospects in reverberation chambers.

[0041] The above description is only a preferred embodiment of the present invention. It should be noted that, for those skilled in the art, equivalent substitutions, improvements and modifications can be made to the design described in the foregoing embodiments without departing from the design scheme and principle of the present invention, and these should all be considered within the protection scope of the present invention.

Claims

1. A foldable reconfigurable stirrer for a reverberation chamber, comprising a foldable metasurface (1), a guide rail motor (2), a guide rail (3), a moving rod (4), and a base plate (5); the foldable metasurface (1) comprises a foldable subarray (11), a moving side plate (6), and a fixed side plate (7); the foldable subarray (11) comprises m*n foldable units (10); the foldable metasurface (1) is located on top of the base plate (5), the moving rod (4) is connected to the moving side plate (6), and the fixed side plate (7) is fixed to the outer edge (51) of the base plate (5); the guide rail (3) is fixed to the bottom edge (53) of the base plate (5) and connected to the fixed side plate (7). Vertical; the guide rail motor (2) can use the guide rail (3) to pull the moving rod (4) back and forth along the guide rail (3) so that the folding metasurface (1) is in an extended or folded state; the moving rod (4) can move in the opposite direction to the outer edge (51) and extend to the maximum extent, at which time the folding metasurface (1) is in an extended state; when the moving rod (4) is not in an extended state, the folding metasurface (1) is in a folded state, and the closer the moving rod (4) is to the outer edge (51), the higher the degree of folding of the folding metasurface (1); the base plate (5) can transmit electromagnetic waves, and the folding unit (10) can transmit part of the electromagnetic waves; When the folded metasurface (1) is in an extended state, the normals of the folding units (10) all point to the normal of the base plate (5); when the folded metasurface (1) is in a folded state, the normals of some folding units (10) point to one direction, and the normals of other folding units (10) point to another direction, and the directions of the two normals are different; by changing the degree of folding of the folded metasurface (1), the normals and folding angles of each folding unit (10) also change, so that the folded metasurface (1) can generate a variety of different distributions of reflection phases, and at the same time generate a variety of different distributions of transmission phases; The folding unit (10) includes an inner metal ring (101), an outer metal ring (102), and a dielectric substrate (103); one side of the dielectric substrate (103) has an inner metal ring (101) and an outer metal ring (102), both of which are square, and are on the same plane. The inner metal ring (101) is located inside the outer metal ring (102), and they are connected by two metal connecting strips (104); this makes the reflection phase of the folding unit (10) related to the incident angle of the incident wave, and also makes the folding unit (101)... The transmission phase of 0) is related to the incident angle of the incident wave; the larger the incident angle of the incident wave, the smaller the reflection phase of the folding unit (10) and the smaller the transmission phase of the folding unit (10); each folding unit (10) has an equivalent polarization axis (105), which is located in the plane containing the inner metal ring (101) and the outer metal ring (102); when the angle between the polarization of the incident wave and the polarization axis (105) changes, the relative magnitude of the amplitude of the reflected wave and the transmitted wave, the reflection phase and the transmission phase all change; by adjusting the angle of the polarization axis (105) of the folding unit (10), the reflection phase and the transmission phase generated by the folding unit (10) can be controlled; In the folded subarray (11), each row of m folded units (10) forms a one-dimensional row array, and the entire folded subarray (11) has n one-dimensional row arrays; in the folded subarray (11), each column of n folded units (10) forms a one-dimensional column array, and the entire folded subarray (11) has m one-dimensional column arrays; in each one-dimensional row array, the polarization axes (105) of adjacent folded units (10) are staggered, and a metal-free dielectric layer fold line is left between adjacent folded units (10), and the folded metasurface (1) is in an extended state. In the extended state, there is a reflection and transmission phase gradient of 360° / m between adjacent folded units (10); in each one-dimensional column array, the polarization axes (105) of adjacent folded units (10) are staggered, and there are metal-free dielectric layer fold lines between adjacent folded units (10). When the folded metasurface (1) is in the extended state, there is a reflection and transmission phase gradient of 360° / n between adjacent folded units (10); the reflected beam can generate beam deflection angle along the row and column directions of the folded subarray (11).

2. A foldable reconfigurable stirrer for a reverberation chamber according to claim 1, characterized in that... The guide rail (3) is kept at a certain distance from the folded metasurface (1) to avoid friction with the folded metasurface (1).

Images