CN206411196U - A kind of microwave dark room - Google Patents
A kind of microwave dark room Download PDFInfo
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- CN206411196U CN206411196U CN201720033109.4U CN201720033109U CN206411196U CN 206411196 U CN206411196 U CN 206411196U CN 201720033109 U CN201720033109 U CN 201720033109U CN 206411196 U CN206411196 U CN 206411196U
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- absorbing material
- dark room
- darkroom
- pyramid
- microwave dark
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Abstract
The utility model discloses a kind of microwave dark room, including electromagnetic shielding chamber, it is installed on the absorbing material of the electromagnetic shielding chamber interior walls and measures antenna, the absorbing material at least top is periodicity pyramid, characterized in that, being located at least in the seamed edge of the pyramid of the absorbing material in the principal reflection area of non-normal incidence in the microwave dark room towards main arrival bearing.The utility model passes through a kind of simple, easy to operate, inexpensive mode, in the case where not changing darkroom structure or absorbing material height, it can just be created a purer measuring environment with high degree reduction darkroom reflection, improve measurement accuracy only by the layout for changing absorbing material.
Description
Technical field
The utility model is related to field of measuring technique, more particularly to a kind of microwave for wireless performance parameter measurement is dark
Room.
Background technology
Microwave dark room also known as without echo room, areflexia room or inhales ripple darkroom (hereinafter referred to as darkroom), is in electromagnetic shielding
Inwall (wall, floor, ceiling etc.) the laying absorbing material of room, effectively absorbs and incides these local electromagnetic waves, reduce
Or eliminate reflection and scatter, so that the free space condition required for forming antenna measurement.Microwave dark room is widely used in antenna
Parameter measurement and the ideal place of electromagnetic wave diffraction, scattering and Radiation biodosimetry.The most basic function of microwave dark room is to carry
For one it is stably and controllable, meet electromagnetic signal environment needed for measurement.According to the difference of absorbing material mounting means, microwave is dark
Room is divided into two kinds of all-wave darkroom, half-wave darkroom.All surface is all covered with absorbing material inside all-wave darkroom, for simulating free sky
Between condition；Half-wave darkroom internal side wall and top surface are covered with absorbing material, and ground is radio wave attenuation face, for simulating open survey
Examination hall.
Absorbing material used in darkroom is nearly all cone, and is mostly pyramid type, and typical pyramid type absorbing material is such as
Shown in Fig. 1, including pedestal and the periodicity pyramid on top.During electromagnetic wave incident to absorbing material, electromagnetic wave the plane of incidence or
Interface can all be reflected, project (refraction) and absorption.The performance of absorbing material directly affects the reflection case inside darkroom.For
The internal reflection of reduction darkroom, common practice is the absorption efficiency for optimizing absorbing material in the prior art, and specific method is main
Including four kinds：(1) addition of wave absorbing agent is increased；(2) increase cone or the height of flat board；(3) darkroom different zones are laid not
With the absorbing material of performance；(4) aerial radiation is reduced to the incident angle of darkroom key reflections area absorbing material.For (1)
For the method for kind, generally, with the increase of wave absorbing agent percentage by volume, inhale ripple efficiency and increased situation is presented, but inhale
The increase of ripple agent has the limit, for conductive material (by taking powdered carbon as an example), and its limit is no more than required lowest frequency
The corresponding skin depth of rate, in addition, it is also contemplated that the influence of coefficient of foaming.For (2) kind method, in general, cone
The height of body is directly proportional to frequency range and absorption efficiency, as height increases, the trend of the usual oriented low-frequency range extension of frequency range,
Its assimilation effect is also of a relatively high, but in order to reach this point, also needs reduction powdered carbon content or phosphorus content is distributed in ladder.With
Upper two methods are limited to the improvement for inhaling ripple efficiency, and can increase the weight and/or height of wave-absorber, also increase simultaneously
Cost.Also, for less darkroom, inner space is limited, it is impossible to use higher absorbing material.Planted for (3)
For method, the absorbing material (in general be height highest) of wall laying peak performance typically behind darkroom, darkroom ground,
Roof and two side walls lay the absorbing material of superior performance, and front wall lays the absorbing material of poorer performance, due to absorbing material
Expensive, this way still can greatly increase cost, and for less darkroom, inner space is limited, nothing
Method uses higher absorbing material.Method is planted for (4), because pyramid type absorbing material aligns the absorbability of incident electromagnetic wave
Can be optimal, and with the increase of incident angle, absorbent properties run down, conventional solution is increase darkroom size so that certain
The incident angle in a little key reflections areas reduces, so that reduce reflection, or the special-shaped absorbing material of design, make at the top of centrum just to entering
The direction of incoming wave is penetrated, being used for as disclosed in CN 104005483B improves the modularization medium fence of microwave dark room quiet zone performance.
This solution can equally increase darkroom manufacturing cost.
In existing darkroom, the placement direction of absorbing material does not make particular design, generally with facilitate installation, reduce waste, it is beautiful
See as criterion.By taking typical rectangle darkroom as an example, as shown in fig. 4 a, for the ease of installing, absorbing material is with similar " laying bricks "
Mode be installed on darkroom inwall.
Utility model content
Main purpose of the present utility model is to overcome the deficiencies in the prior art there is provided a kind of microwave dark room, only by changing
Reflecting background inside darkroom is greatly reduced there is provided a pure measuring environment in the layout type for becoming absorbing material, improves and surveys
The accuracy of amount.
To achieve the above object, the utility model first aspect embodiment proposes a kind of technical scheme：
A kind of microwave dark room, including electromagnetic shielding chamber, be installed on it is described electromagnetic shielding chamber interior walls absorbing material and measurement
Antenna, the absorbing material at least top is periodicity pyramid, it is characterised in that be located at least in the microwave dark room non-perpendicular
The seamed edge of the pyramid of the absorbing material in incident principal reflection area is towards main arrival bearing.
Further, the rib of the pyramid of the absorbing material in the principal reflection area of non-normal incidence is located at least in the microwave dark room
Side is just to main arrival bearing.
Further, the seamed edge of pyramid of absorbing material around antenna is measured in the microwave dark room towards main incoming wave side
To.
Further, the seamed edge of the pyramid of the absorbing material in the microwave dark room around measurement antenna is just to main incoming wave side
To.
Further, the seamed edge direction that the pyramid of the absorbing material around antenna is measured in the microwave dark room closes on measurement day
The direction of line.
Further, the seamed edge of the pyramid of the absorbing material in the microwave dark room around measurement antenna is just to closing on measurement day
The direction of line.
The utility model second aspect embodiment proposes a kind of technical scheme：
A kind of microwave dark room, including electromagnetic shielding chamber, be installed on it is described electromagnetic shielding chamber interior walls absorbing material and measurement
Antenna, the absorbing material at least top is periodicity pyramid, it is characterised in that the measurement antenna is at least partially disposed in suction ripple
In material, the center overlapping of axles of the central shaft and the one of pyramid of the absorbing material of the measurement antenna.
The utility model is not changing darkroom structure or absorbing material by a kind of simple, easy to operate, inexpensive mode
In the case of height, just one can be created more with high degree reduction darkroom reflection only by the layout for changing absorbing material
Pure measuring environment, improves measurement accuracy.
Brief description of the drawings
The above-mentioned and/or additional aspect of the utility model and advantage from the following description of the accompanying drawings of embodiments will
Become substantially and be readily appreciated that, wherein：
Fig. 1 is a kind of typical absorbing material schematic diagram；
Fig. 2 is principal reflection area schematic diagram in rectangle darkroom, absorbing material not shown in figure；
Fig. 3 is the principal reflection area schematic diagram of non-normal incidence in rectangle darkroom, absorbing material not shown in figure；
Fig. 4 a are the schematic layout pattern of absorbing material in existing rectangle darkroom；
When Fig. 4 b are the principal reflection area of electromagnetic wave arrival non-normal incidence of measurement antenna transmitting in existing rectangle darkroom
Incident schematic diagram, part absorbing material is only shown in figure；
When Fig. 4 c are the principal reflection area of electromagnetic wave arrival non-normal incidence of measurement antenna transmitting in existing rectangle darkroom
Local incident schematic diagram；
Fig. 5 a are that the master of the electromagnetic wave arrival non-normal incidence of measurement antenna transmitting in the darkroom of the utility model embodiment 1 is anti-
Penetrate in incident schematic diagram during area, figure and part absorbing material is only shown；
Fig. 5 b are that the master of the electromagnetic wave arrival non-normal incidence of measurement antenna transmitting in the darkroom of the utility model embodiment 1 is anti-
Penetrate local incident schematic diagram during area；
Fig. 5 c are that the master of the electromagnetic wave arrival non-normal incidence of measurement antenna transmitting in the darkroom of the utility model embodiment 1 is anti-
Penetrate a kind of local incident top view of angle during area；
Fig. 5 d are that the master of the electromagnetic wave arrival non-normal incidence of measurement antenna transmitting in the darkroom of the utility model embodiment 1 is anti-
Penetrate the local incident top view of another angle during area；
Fig. 6 is a kind of absorbing material layout type schematic diagram of the utility model embodiment 1；
Fig. 7 is a kind of schematic appearance in cylindrical Multi probe darkroom；
Fig. 8 be existing cylindrical Multi probe darkroom in measurement antenna around absorbing material schematic layout pattern；
Fig. 9 a be the darkroom of the utility model embodiment 2 in measurement antenna around absorbing material schematic layout pattern；
Fig. 9 b be the darkroom of the utility model embodiment 2 in measurement antenna around absorbing material layout partial schematic diagram；
Figure 10 a be the darkroom of the utility model embodiment 3 in measurement antenna around absorbing material schematic layout pattern；
Figure 10 b be the darkroom of the utility model embodiment 3 in measurement antenna around absorbing material layout top view；
Figure 11 a be existing darkroom in measurement antenna around absorbing material schematic layout pattern；
Figure 11 b be existing darkroom in measurement antenna around absorbing material layout top view.
Embodiment
Embodiment of the present utility model is elaborated below.It is emphasized that the description below is only example
Property, it is intended to for explaining the utility model, and it is not intended that to limitation of the present utility model.
In addition, term " first ", " second " are only used for describing purpose, and it is not intended that indicating or implying relative importance
Or the implicit quantity for indicating indicated technical characteristic.Thus, define " first ", the feature of " second " can express or
Implicitly include one or more this feature.In description of the present utility model, " multiple " are meant that two or two
More than, unless otherwise specifically defined.
In the utility model, unless otherwise clearly defined and limited, term " installation ", " connected ", " connection ", " Gu
It is fixed " etc. term should be interpreted broadly, for example, it may be being fixedly connected or being detachably connected, or be integrally connected；Can
To be mechanical connection or electrical connection；Can be joined directly together, can also be indirectly connected to by intermediary, Ke Yishi
The connection of two element internals.For the ordinary skill in the art, above-mentioned term can be understood as the case may be
Concrete meaning in the utility model.
In the utility model, unless otherwise clearly defined and limited, fisrt feature second feature it " on " or it
" under " can directly be contacted including the first and second features, it is not direct contact but logical that can also include the first and second features
The other characterisation contact crossed between them.Moreover, fisrt feature second feature " on ", " top " and " above " include the
One feature is directly over second feature and oblique upper, or is merely representative of fisrt feature level height higher than second feature.First is special
Levy second feature " under ", " lower section " and " below " include fisrt feature directly over second feature and oblique upper, or only
Represent that fisrt feature level height is less than second feature.
Microwave dark room (hereinafter referred to as " darkroom ") of the present utility model includes electromagnetic shielding chamber, is installed on the electromagnetic shielding
The absorbing material and measurement antenna of chamber interior walls, the absorbing material at least top is periodicity pyramid, refering to Fig. 1, current darkroom
In used absorbing material be almost this kind of pyramid type absorbing material, including pedestal and the periodicity pyramid on top.It is well known that
There is principal reflection area and secondary reflection area in darkroom, determine the reflection case in the mainly principal reflection area of reflection noise in darkroom.It is logical
Often for, it is believed that in darkroom measure antenna transmitting electromagnetic wave by primary event can reach measurement dead zone reflector space be
Principal reflection area, can determine the principal reflection area in darkroom, or determine by Fresnel principle using ray casting in the prior art
Darkroom is in the principal reflection area of each reflecting surface.But because the reflection characteristic in different darkrooms is different, it is determined that during principal reflection area,
According to the concrete condition in darkroom, it is also required to consider secondary reflection even triple reflection sometimes.
Rectangle darkroom is most common simple shape, widely used darkroom.Refering to Fig. 2, rectangle darkroom includes 6 faces：
The top surface where antenna 101 is measured, measurement antenna opposite is close to the bottom surface of measured zone 102 and 4 sides, in general, square
The first principal reflection area 201 that principal reflection area in shape darkroom is included on 4 sides (only shows the first master on 2 sides in Fig. 2
Echo area 201, the position in the first principal reflection area on remaining 2 side can be readily recognized by prior art) and bottom surface on
The second principal reflection area 202.Wherein, the second principal reflection area 202 is the principal reflection area of vertical incidence, that is, measures the electricity of antenna transmitting
Incidence angle of the magnetic wave in the region is 90 degree；First principal reflection area 201 is the principal reflection area of non-normal incidence, that is, measures antenna hair
Incidence angle of the electromagnetic wave penetrated in the region is not 90 degree, as shown in Figure 3.
In existing rectangle darkroom, the placement direction of absorbing material does not make particular design, generally with facilitate installation, reduce wave
Take, it is attractive in appearance be criterion.As shown in fig. 4 a, for the ease of installing, absorbing material is to be installed on darkroom in the way of similar " laying bricks "
Inwall.In this case, it is that the first master is anti-that the electromagnetic wave that measurement antenna 101 is launched, which is reached positioned at the principal reflection area of non-normal incidence,
When penetrating the absorbing material in area 201, as shown in Fig. 4 b and Fig. 4 c, electromagnetic wave enters on the side plane of the top pyramid of absorbing material
Penetrate, according to propagation properties, when incident interface is plane, the two media drastic impedance variations at incident interface, electromagnetism
Wave reflection is stronger.
The angle of the absorbing material in the principal reflection area of non-normal incidence is located at least in the utility model embodiment 1, in darkroom
The seamed edge of cone is towards main arrival bearing.Specifically, refering to Fig. 5 a-5d, the first principal reflection area 201 in darkroom be it is non-perpendicular enter
The principal reflection area penetrated, main arrival bearing is the direction for measuring the principal reflection of antenna 101 to the first area 201.It is described " to be located at non-perpendicular
The seamed edge of the pyramid of the absorbing material in incident principal reflection area is towards main arrival bearing " be interpreted as measurement antenna 101 launch to
The electromagnetic wave in the first principal reflection area 201 first reaches the seamed edge of the pyramid of the absorbing material positioned at the first principal reflection area 201.Wherein,
Fig. 5 d show a kind of more excellent embodiment, i.e., described seamed edge is just to main arrival bearing, and " just to " is interpreted as main incoming wave
Angle α between two planes adjacent with seamed edge of direction is equal.According to propagation properties, when incident interface is corner angle
When, the two media impedance at incident interface is capable of realizing impedance matching in the ideal case compared to being gradual change for plane, so that
The reflection of electromagnetic wave is dramatically reduced, wherein for " just to " is compared to " direction ", impedance variations are more gentle, therefore
Reflection is smaller.
On the other hand, refering to Fig. 5 a, the around measurement antenna 101 the 3rd is located in the utility model embodiment 1, in darkroom
The seamed edge of the pyramid of the absorbing material in region 203 towards or just to the situation of (shown in Fig. 5 a for " just to ") main incoming wave side
To main arrival bearing is the direction for measuring the first principal reflection area 201 on 101 to 4 sides of antenna.This layout can be reduced
The electromagnetic wave in the first principal reflection area 201 is reached, is also believed to reduce the beam angle of measurement antenna 101.
The above-mentioned particular topology of absorbing material is only for the first principal reflection area 201 and the 3rd region 203, other areas in Fig. 5 a
The absorbing material in domain can retain conventional in layout mode, or, for the ease of the installation of absorbing material, the wave of reduction absorbing material
Take, can be by layout type of the absorbing material all in darkroom by absorbing material in the first principal reflection area 201 and the 3rd region 203
Unified layout is carried out, as shown in fig. 6, being regarded as the absorbing material (as shown in fig. 4 a) in traditional darkroom along each mounting surface
Normal have rotated 45 degree.Simulation result and actual measured results are shown, in same dark room conditions, dark shown in Fig. 5 a
The internal reflection noise in room and the darkroom shown in Fig. 6 is respectively less than the darkroom shown in Fig. 4 a.
For another cylindrical Multi probe darkroom, a kind of schematic appearance in this kind of darkroom is illustrated in figure 7.
For Multi probe darkroom, especially small-sized Multi probe darkroom, due to existing between multiple measurement antennas, measurement antenna
Reflection is the absorbing material layout around measurement antenna 101 in a great noise source in darkroom, existing such darkroom
As shown in Figure 8.In the utility model embodiment 2, as shown in Fig. 9 a-9b, the 4th area around antenna 101 is measured in darkroom
The seamed edge of the pyramid of the absorbing material in domain 204 towards or measurement day just is being closed on to the situation of (shown in Fig. 9 a-9b for " just to ")
The direction of line 101, it is believed that be that have rotated normal of the absorbing material (as shown in Figure 8) along each mounting surface in traditional darkroom
45 degree, such a absorbing material layout can effectively reduce the reflecting background closed between measurement antenna.
It is worth noting that, in Multi probe darkroom, the different cloth of the absorbing material described in embodiment 1 and embodiment 2
Office's mode, which should try one's best, to be taken into account, and as being difficult to take into account, is selected according to the specific reflected intensity of different zones in darkroom.
On the other hand, refering to Figure 10 a-10b, in embodiment 3, measurement antenna 101 is at least partially disposed in absorbing material, is surveyed
Measure the central shaft of antenna 101 and the center overlapping of axles of the one of pyramid 301 of the absorbing material.It should be noted that pyramid
301 be a virtual pyramid, and at least part of pyramid 301 is removed for placing antenna during actual installation absorbing material.Embodiment 3
Layout type can make measurement antenna 101 launch electromagnetic wave in all directions can be to a certain extent by the suction ripple of surrounding
Material absorbs.It is the installation site that antenna 101 is measured in existing darkroom as shown in Figure 11 a-11b：Measure the central shaft of antenna 101
Positioned at absorbing material close on pyramid between " ten " word junction 401.The shortcoming of this layout is to measure the electricity that antenna 101 is launched
Magnetic wave is blocked on 4 directions of " ten " word of " ten " word junction 401 without absorbing material, so as to may be deposited in this 4 directions
In serious radiation, and then measurement noise is produced, for cross polarization measurement antenna, if 4 sides of " ten " word
To just identical with measuring the polarised direction of antenna, meeting is radiated stronger.
Above-described embodiment only lists two conventional class darkrooms and illustrated, and the utility model is equally applicable to other types
Darkroom such as taper darkroom, semicircle darkroom, T-shaped darkroom, complex darkroom etc..Measurement day described in above-described embodiment
Line can be any type of measurement antenna, such as single-polarized antenna, cross polarised antenna, circular polarized antenna.In accompanying drawing
The quantity and height of absorbing material are only signal effects, not actual laying number and height ratio.
Above content is to combine specific/preferred embodiment further detailed description of the utility model, no
It can assert that specific implementation of the present utility model is confined to these explanations.For the common skill of the utility model art
For art personnel, without departing from the concept of the premise utility, it can also make to the embodiment that these have been described
Some replacements or modification, and these are substituted or variant should all be considered as belonging to protection domain of the present utility model.
Claims (7)
1. a kind of microwave dark room, including electromagnetic shielding chamber, the absorbing material and measurement day that are installed on the electromagnetic shielding chamber interior walls
Line, the absorbing material at least top be periodicity pyramid, it is characterised in that be located at least in the microwave dark room it is non-perpendicular enter
The seamed edge of the pyramid of the absorbing material in the principal reflection area penetrated is towards main arrival bearing.
2. microwave dark room as claimed in claim 1, it is characterised in that be located at least in non-normal incidence in the microwave dark room
The seamed edge of the pyramid of the absorbing material in principal reflection area is just to main arrival bearing.
3. microwave dark room as claimed in claim 1 or 2, it is characterised in that the suction around antenna is measured in the microwave dark room
The seamed edge of the pyramid of wave material is towards main arrival bearing.
4. microwave dark room as claimed in claim 3, it is characterised in that the suction ripple material around antenna is measured in the microwave dark room
The seamed edge of the pyramid of material is just to main arrival bearing.
5. microwave dark room as claimed in claim 1 or 2, it is characterised in that the suction around antenna is measured in the microwave dark room
The seamed edge of the pyramid of wave material measures the direction of antenna towards closing on.
6. microwave dark room as claimed in claim 5, it is characterised in that the suction ripple material around antenna is measured in the microwave dark room
Direction of the seamed edge of the pyramid of material just to closing on measurement antenna.
7. a kind of microwave dark room, including electromagnetic shielding chamber, the absorbing material and measurement day that are installed on the electromagnetic shielding chamber interior walls
Line, the absorbing material at least top is periodicity pyramid, it is characterised in that the measurement antenna is at least partially disposed in suction ripple material
In material, the center overlapping of axles of the central shaft and the one of pyramid of the absorbing material of the measurement antenna.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720033109.4U CN206411196U (en) | 2017-01-12 | 2017-01-12 | A kind of microwave dark room |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201720033109.4U CN206411196U (en) | 2017-01-12 | 2017-01-12 | A kind of microwave dark room |
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| Publication Number | Publication Date |
|---|---|
| CN206411196U true CN206411196U (en) | 2017-08-15 |
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ID=59554800
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
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| CN201720033109.4U Active CN206411196U (en) | 2017-01-12 | 2017-01-12 | A kind of microwave dark room |
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| CN (1) | CN206411196U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106597129A (en) * | 2017-01-12 | 2017-04-26 | 深圳市通用测试系统有限公司 | Microwave anechoic chamber |
| CN116859135A (en) * | 2023-08-31 | 2023-10-10 | 辽宁信鼎检测认证有限公司 | Communication contrast test system suitable for wireless product |
-
2017
- 2017-01-12 CN CN201720033109.4U patent/CN206411196U/en active Active
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106597129A (en) * | 2017-01-12 | 2017-04-26 | 深圳市通用测试系统有限公司 | Microwave anechoic chamber |
| CN106597129B (en) * | 2017-01-12 | 2024-02-02 | 深圳市通用测试系统有限公司 | Microwave darkroom |
| CN116859135A (en) * | 2023-08-31 | 2023-10-10 | 辽宁信鼎检测认证有限公司 | Communication contrast test system suitable for wireless product |
| CN116859135B (en) * | 2023-08-31 | 2023-10-31 | 辽宁信鼎检测认证有限公司 | Communication contrast test system suitable for wireless product |
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