CN113109635A - Reflecting surface and compact range measuring system with same - Google Patents
Reflecting surface and compact range measuring system with same Download PDFInfo
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- CN113109635A CN113109635A CN202110561491.7A CN202110561491A CN113109635A CN 113109635 A CN113109635 A CN 113109635A CN 202110561491 A CN202110561491 A CN 202110561491A CN 113109635 A CN113109635 A CN 113109635A
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- electromagnetic wave
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- reflective surface
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R29/00—Arrangements for measuring or indicating electric quantities not covered by groups G01R19/00 - G01R27/00
- G01R29/08—Measuring electromagnetic field characteristics
- G01R29/10—Radiation diagrams of antennas
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Abstract
The present disclosure provides a reflective surface, comprising a reflective surface body for reflecting electromagnetic waves; a semiconductor part connected to an edge of the reflection surface body and extending outward; and the electromagnetic wave absorption part is connected with the semiconductor part and extends outwards, and the electromagnetic wave absorption part adopts a wave-absorbing material. The present disclosure also provides a compact range measurement system having the reflective surface. The edge current of the reflecting surface body is conducted to the semiconductor part, and the semiconductor part and the electromagnetic wave absorption part connected with the semiconductor part absorb and lose the electromagnetic energy, so that the diffraction effect of the edge of the reflecting surface is reduced, and the quiet area performance is improved.
Description
Technical Field
The invention relates to the field of compact range measurement, in particular to a reflecting surface and a compact range measuring system with the reflecting surface.
Background
The compact range measuring system converts spherical waves emitted by the feed source antenna into plane waves through a lens or a reflecting surface, and simulates the electromagnetic environment of the plane waves of a far field in a small space, namely the change of the amplitude and the phase in a quiet zone range meets the requirement of antenna measurement on the plane wave irradiation environment. If the reflecting surface is an infinite paraboloid, the spherical electromagnetic wave emitted by the feed source antenna can be completely converted into plane wave theoretically and reflected to the measuring area. However, in practical applications, the size of the reflecting surface is limited, and diffraction effects from the edge of the reflecting surface can cause non-planar waves to appear, which can reduce the measurement accuracy in the dead zone range.
This problem is solved in the related art by providing the edge of the reflecting surface with a saw-tooth structure or by hemming the edge of the reflecting surface, both types of edge structures being capable of guiding energy impinging on the edge of the reflecting surface away from the measuring region.
Disclosure of Invention
The present disclosure describes a reflective surface and a compact range measurement system having the reflective surface.
According to a first aspect of embodiments of the present disclosure, there is provided a reflective surface comprising: the reflecting surface body is used for reflecting electromagnetic waves; a semiconductor part connected to an edge of the reflection surface body and extending outward; and the electromagnetic wave absorption part is connected with the semiconductor part and extends outwards, and the electromagnetic wave absorption part adopts a wave-absorbing material.
According to an embodiment of the reflective surface, the semiconductor part is connected to a side face of an edge of the reflective surface body, or the semiconductor part is connected to a working face of an edge of the reflective surface body, the working face being the face of the reflective surface body for reflecting electromagnetic waves.
According to one embodiment of the reflecting surface, the semiconductor section is smoothly connected to an edge of the reflecting surface body, and the electromagnetic wave absorbing section is smoothly connected to the semiconductor section.
According to one embodiment of the reflection surface, the electromagnetic wave absorption portion has a length of 0.5 to 5 times the wavelength of the electromagnetic wave.
According to an embodiment of the reflective surface, the resistance of the part of the semiconductor section that is connected to the edge of the reflective surface body is smaller than the resistance of the end portion of the semiconductor section that extends outwards.
According to one embodiment of the reflecting surface, the electromagnetic wave absorbing portion has an impedance gradation structure in a direction extending outward.
According to one embodiment of the reflecting surface, the impedance grading structure is: the outward extending end of the electromagnetic wave absorbing part forms at least one zigzag shape.
According to one embodiment of the reflective surface, the edge of the reflective surface body is serrated.
According to a second aspect of embodiments of the present disclosure, there is provided a compact range measurement system, comprising: anechoic chamber, feed source antenna, and the aforementioned reflecting surface.
According to one embodiment of the compact range measurement system, the electromagnetic wave absorbing portion of the reflective surface extends outward to a sidewall of the anechoic chamber.
In the reflecting surface of the embodiment of the disclosure, the edge current of the reflecting surface body is conducted to the semiconductor part, and the semiconductor part and the electromagnetic wave absorption part connected with the semiconductor part absorb and lose the electromagnetic energy, so that the diffraction effect of the edge of the reflecting surface is reduced, and the quiet zone performance is improved.
Drawings
FIG. 1a illustrates a front view of a reflective surface of the present disclosure according to one embodiment.
FIG. 1b illustrates a front view of a reflective surface of the present disclosure according to one embodiment.
FIG. 2a illustrates a partial cross-sectional view of a reflective surface of the present disclosure according to one embodiment.
FIG. 2b illustrates a partial cross-sectional view of a reflective surface of the present disclosure according to one embodiment.
FIG. 3a illustrates a partial cross-sectional view of a reflective surface of the present disclosure according to one embodiment.
FIG. 3b illustrates a partial cross-sectional view of a reflective surface of the present disclosure according to one embodiment.
FIG. 3c illustrates a partial cross-sectional view of a reflective surface of the present disclosure according to one embodiment.
FIG. 4 illustrates a cross-sectional view of a reflective surface of the present disclosure according to one embodiment.
FIG. 5 illustrates a cross-sectional view of a reflective surface of the present disclosure according to one embodiment.
FIG. 6 illustrates a front view of a reflective surface of the present disclosure according to one embodiment.
Detailed Description
Embodiments of the present disclosure are described below with reference to the drawings. It should be understood that the drawings are not necessarily to scale. The described embodiments are exemplary and not intended to limit the present disclosure, which features may be combined with or substituted for those of the embodiments in the same or similar manner. As used in this disclosure and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and/or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.
The compact range measuring system converts spherical waves emitted by the feed source antenna into plane waves through a lens or a reflecting surface, and simulates the electromagnetic environment of the plane waves of a far field in a small space, namely, the amplitude and phase change in a quiet zone range meets the requirements of antenna measurement on the plane wave irradiation environment. If the reflecting surface is an infinite paraboloid, the spherical electromagnetic wave emitted by the feed source antenna can be completely converted into a plane wave theoretically and reflected to the measuring area. However, in practice, the size of the reflecting surface is limited, and diffraction or scattering effects from the edge of the reflecting surface can cause non-planar waves to appear, which can reduce the measurement accuracy in the dead zone range.
Diffraction is in fact a phenomenon in which electromagnetic signals can propagate around curved or sharp-edged obstacles, based on the huygens principle, which states that each point on the wavefront acts as a secondary point source, i.e. diffraction is caused by a secondary wavelet.
There are two main approaches to solving the edge diffraction problem in the related art: the edge of the reflecting surface is designed into a sawtooth structure so as to reduce the edge diffraction effect; or the edge of the reflecting surface is curled according to a certain curve function so as to reduce the influence on the incident wave.
The reflective surface and the compact range measurement system having the reflective surface of the embodiments of the present disclosure are described below with reference to the accompanying drawings.
Referring to fig. 1a, an embodiment in one aspect of the present disclosure provides a reflective surface, which includes a reflective surface body 100 for reflecting electromagnetic waves, and further includes a semiconductor portion 200 and an electromagnetic wave absorption portion 300 disposed at an edge of the reflective surface body 100. The semiconductor part 200 is connected to the edge of the reflector body 100 and extends outward, the electromagnetic wave absorbing part 300 is connected to the semiconductor part 200 and extends outward, and the electromagnetic wave absorbing part 300 is made of wave absorbing material.
The edge structure and the action of the reflecting surface of the present embodiment are exemplified here. Referring to fig. 1a, the semiconductor part 200 is connected to and extends outward from an edge of the reflective surface body 100, an edge current of the reflective surface body 100 is conducted to the semiconductor part 200, and the semiconductor part 200 has a certain absorption and loss effect on the edge electromagnetic energy. In addition, the semiconductor portion 200 is connected to the electromagnetic wave absorption portion 300, and the electromagnetic wave absorption portion 300 further absorbs and loses the electromagnetic energy, thereby avoiding or reducing a diffraction effect generated at the edge of the reflection surface body 100. Specific implementations of what has been said to be "connected" include, but are not limited to: adhesive bonding, snap-fitting, joining using a connector, intimate contact but loose connection, and the like. The structure of the reflecting surface in the present disclosure is not limited to that shown in fig. 1 a. Specifically, the reflective surface body may be designed to have a special shape, and referring to fig. 1b, the edge of the reflective surface body 100 may be a zigzag shape in the related art. The semiconductor portion and the electromagnetic wave absorbing portion may have a designed special shape, for example, referring to fig. 1b, in order to adapt to the shape of the reflection surface main body 100, one end of the semiconductor portion 200 connected to the edge of the reflection surface main body 100 is set to have a corresponding shape. Alternatively, the electromagnetic wave absorbing section is provided with an impedance gradation structure for enhancing absorption and loss of energy, and the like.
The manner in which the semiconductor section is connected to the edge of the reflecting surface body in some embodiments will now be described with reference to fig. 2a-2 b. Fig. 2a-2b each illustrate a partial cross-sectional view of a reflecting surface in different embodiments.
Referring to fig. 2a, optionally, in some embodiments, the semiconductor portion 200 is connected to the side 101 of the edge of the reflective surface body 100. It will be appreciated that the reflector body is typically a metal structure having a thickness, the side of the edge of the reflector body being the side corresponding to its thickness.
Referring to fig. 2b, optionally, in other embodiments, the semiconductor portion 200 is connected to the working surface 102 at the edge of the reflective surface body 100, and the working surface 102 is the surface of the reflective surface body 100 for reflecting electromagnetic waves. It will be appreciated that the working face of the reflector body is the face facing the feed. The semiconductor section is directly connected to the working surface of the edge of the reflecting surface body, and the edge current can be more sufficiently conducted from the reflecting surface body to the semiconductor section.
The connection between the electromagnetic wave absorbing part and the semiconductor part in some embodiments will be described with reference to fig. 3a to 3 c. Fig. 3a-3c each illustrate a partial cross-sectional view of a reflective surface in different embodiments.
Referring to fig. 3a, optionally, in some embodiments, the electromagnetic wave absorption part 300 is connected to the side surface 201 of the end of the semiconductor part 200 extending outward. Similarly, the side face of the semiconductor portion is the one corresponding to the thickness thereof.
Referring to fig. 3b, optionally, in some embodiments, the electromagnetic wave absorption part 300 is connected to the non-side surface 202 of the end of the semiconductor part 200 extending outward. The non-side surface of the semiconductor portion is any surface other than the side surface.
Referring to fig. 3c, optionally, in some embodiments, the electromagnetic wave absorption part 300 is connected to the end of the semiconductor part 200 extending outward in a cladding manner, which is equivalent to the end of the semiconductor part 200 extending outward embedding the electromagnetic wave absorption part 300.
Alternatively, the semiconductor section is smoothly connected to the edge of the reflection surface body, and the electromagnetic wave absorption section is smoothly connected to the semiconductor section. The smooth connection can enable the conducting path of the current to have good flatness on one hand, signal echoes caused by impedance sudden change are avoided, and on the other hand, the good impedance continuity can enable the energy to be slowly attenuated. Specifically, referring to fig. 4, as an example, the reflecting surface body 100, the semiconductor section 200, and the electromagnetic wave absorbing section 300 have the same curve formula. As another example, the semiconductor portion and the electromagnetic wave absorbing portion smoothly extend toward the back surface of the working surface of the reflection surface body, forming a shape like a hemming-shaped reflection surface in the related art to guide a small amount of scattered energy out of the measurement region.
In order to ensure the loss of the energy to the edge, the length of the electromagnetic wave absorption part can be set to be 0.5 to 5 times of the wavelength of the electromagnetic wave, and the length of the electromagnetic wave absorption part can be understood as the distance extending outwards from the electromagnetic wave absorption part. Further, it is also possible to make the contact area where the semiconductor section is connected to the reflection surface body as large as possible so that the edge current of the reflection surface body is sufficiently conducted to the semiconductor section, and to make the contact area where the electromagnetic wave absorbing section is connected to the semiconductor section as large as possible so as to ensure sufficient absorption and loss of energy by the electromagnetic wave absorbing section. For example, the manner in which the semiconductor section 200 is connected to the edge of the reflective surface body 100 in fig. 2b can generally achieve a larger contact area than the manner of connection in fig. 2 a; the connection of the electromagnetic wave absorption part 300 to the semiconductor part 200 in fig. 3b and 3c generally provides a larger contact area than the connection in fig. 3 a. As another example, referring to fig. 5, one end of the semiconductor section 200 is connected to the working surface 102 of the edge of the reflective surface body 100, the other end of the semiconductor section 200 is connected to the electromagnetic wave absorption section 300, and one end of the electromagnetic wave absorption section 300 reaches the edge 101 of the reflective surface body 100, which ensures both the contact area between the semiconductor section 200 and the reflective surface body 100 and the contact area between the electromagnetic wave absorption section 300 and the semiconductor section 200.
Optionally, in some embodiments, a resistance value of a portion of the semiconductor section connected to the edge of the reflective surface body is smaller than a resistance value of an end portion of the semiconductor section extending outward. Therefore, the outward impedance gradual change from the edge of the reflecting surface body can be formed, the distribution that the intensity of the current generated by the electromagnetic wave on the metal surface is large at the center and the intensity of the edge is small is met, and the gradient impedance matching is realized.
Alternatively, in some embodiments, the electromagnetic wave absorption portion has an impedance gradation structure in a direction extending outward. Referring to fig. 6, as an example, the impedance gradual change structure is: the end of the electromagnetic wave absorption part 300 extending outward forms at least one zigzag structure 301.
Another aspect embodiment of the present disclosure provides a compact range measurement system, comprising: anechoic chamber, feed antenna, and reflecting surface as described above.
Optionally, in some embodiments of the compact range measurement system, the electromagnetic wave absorbing portion of the reflective surface extends outward to a sidewall of the anechoic chamber. For example, to the wave-absorbing material of the side walls of the anechoic chamber, or to the shielding housing of the anechoic chamber. On one hand, the area/number of the electromagnetic wave absorption parts is further increased, so that the absorption and loss are enhanced, on the other hand, the boundary of the reflection surface is blurred, so that the scattering effect of the electromagnetic waves at the edge is further weakened, and the adverse effect on a dead zone is further reduced.
It should be noted that the drawings in the present disclosure are simplified schematic drawings, and are only used for schematically illustrating the positional relationship and the connection relationship between the parts in the embodiments.
In the description above, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In the present disclosure, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present disclosure, "a plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise.
Although embodiments of the present disclosure have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present disclosure, and that changes, modifications, substitutions and alterations may be made to the above embodiments by those of ordinary skill in the art within the scope of the present disclosure.
Claims (10)
1. A reflective surface, comprising:
the reflecting surface body is used for reflecting electromagnetic waves;
a semiconductor part connected to an edge of the reflective surface body and extending outward; and
and the electromagnetic wave absorption part is connected with the semiconductor part and extends outwards, and the electromagnetic wave absorption part adopts a wave-absorbing material.
2. The reflecting surface according to claim 1, wherein the semiconductor portion is connected to a side surface of an edge of the reflecting surface body, or the semiconductor portion is connected to a working surface of the edge of the reflecting surface body, the working surface being a surface of the reflecting surface body for reflecting electromagnetic waves.
3. The reflecting surface according to claim 1, wherein the semiconductor portion is smoothly connected to an edge of the reflecting surface body, and the electromagnetic wave absorbing portion is smoothly connected to the semiconductor portion.
4. The reflection surface according to claim 1, wherein the electromagnetic wave absorption portion has a length of 0.5 to 5 times a wavelength of the electromagnetic wave.
5. The reflective surface of claim 1, wherein a portion of said semiconductor portion connected to an edge of said reflective surface body has a resistance value less than a resistance value of an outwardly extending end portion of said semiconductor portion.
6. The reflecting surface according to claim 1, wherein the electromagnetic wave absorbing portion has an impedance gradation structure in a direction extending outward.
7. The reflective surface of claim 6, wherein said impedance tapering structure is: the outward extending end of the electromagnetic wave absorption part forms at least one zigzag shape.
8. The reflective surface of any of claims 1-7, wherein the edges of said reflective surface body are serrated.
9. A compact range measurement system, comprising: anechoic chamber, feed antenna, and a reflective surface according to any one of claims 1 to 8.
10. The compact range measurement system of claim 9, wherein the electromagnetic wave absorbing portion of the reflective surface extends outward to a sidewall of the anechoic chamber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202110561491.7A CN113109635A (en) | 2021-05-22 | 2021-05-22 | Reflecting surface and compact range measuring system with same |
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| CN202110561491.7A CN113109635A (en) | 2021-05-22 | 2021-05-22 | Reflecting surface and compact range measuring system with same |
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