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EP0377879A1 - Plane elements for the absorption or reduction of the reflection of electromagnetic waves - Google Patents

Plane elements for the absorption or reduction of the reflection of electromagnetic waves Download PDF

Info

Publication number
EP0377879A1
EP0377879A1 EP89123647A EP89123647A EP0377879A1 EP 0377879 A1 EP0377879 A1 EP 0377879A1 EP 89123647 A EP89123647 A EP 89123647A EP 89123647 A EP89123647 A EP 89123647A EP 0377879 A1 EP0377879 A1 EP 0377879A1
Authority
EP
European Patent Office
Prior art keywords
electromagnetic waves
structure according
electrically conductive
facade
facade structure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP89123647A
Other languages
German (de)
French (fr)
Inventor
Joachim Bettermann
Dirk Bringmann
Andreas Dr. Frye
Jürgen Kruse
Julius Weyand
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Airbus Defence and Space GmbH
Original Assignee
Deutsche Aerospace AG
Messerschmitt Bolkow Blohm AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Deutsche Aerospace AG, Messerschmitt Bolkow Blohm AG filed Critical Deutsche Aerospace AG
Publication of EP0377879A1 publication Critical patent/EP0377879A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q17/00—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
    • H01Q17/004—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems using non-directional dissipative particles, e.g. ferrite powders

Definitions

  • the invention relates to a facade structure of high-rise buildings, such as buildings, in particular in thin-layer construction, the outer regions being formed by surface elements.
  • the object of the invention is to provide a facade structure of the generic type that allows reflection damping or absorption of the electromagnetic waves that occur in a simple manner and thus avoids interference with directional radio links and ASR systems.
  • coatings of absorbent material for the electromagnetic waves are arranged in the outer region in front of components reflecting electromagnetic waves, said material consisting of an electrical non-conductor, in which electrically conductive and / or magnetic materials for forming conductivity regions are embedded, whose dimensions in all levels are at least 1000 times less than the wavelength of the electromagnetic waves to be absorbed and the electrically conductive and / or magnetic materials make up up to 40% of the weight of the coating.
  • the impinging waves are essentially absorbed or damped by the conductivity regions formed, in that the energy contained is converted into heat.
  • the surface elements are formed by a plastic as an electrical non-conductor and soot particles are arranged as an electrically conductive material.
  • carbonyl iron powder can be used as the magnetic material.
  • the surfaces on which the electromagnetic waves reflect are structured in such a way that subtraction can be carried out by different transit times of the reflected electromagnetic wave components.
  • a special design is that the surfaces on which the electromagnetic waves reflect have a deep structure, such as a grooved surface.
  • the coating is formed from several layers and the electrically conductive and / or magnetic materials have different parts by weight.
  • a metallic grating is arranged as an antenna for reflection before the inspection and that a subtraction can be carried out by different transit times of the reflecting electromagnetic wave components.
  • This construction according to the invention makes it possible to eliminate the problems of the disturbing reflection of high-rise buildings.
  • the surface elements with coatings are usually fastened to the structure in accordance with the proposed structure, protective layers made of electrical non-conductors being additionally able to be applied or connected upstream in order to form a facade exterior formed from a different material.
  • the electrically conductive and / or magnetic materials introduced into the surface elements are transformed into electrical waste materials introduced non-conductive materials. This can optionally be done in the manufacturing process.
  • conductivity areas are dimensioned according to the wavelength of the waves to be absorbed.
  • the coating can be applied by flame spraying / plasma spraying. Alternatively, of course, several partial layers can be built up by roll cladding.

Landscapes

  • Shielding Devices Or Components To Electric Or Magnetic Fields (AREA)
  • Building Environments (AREA)
  • Aerials With Secondary Devices (AREA)

Abstract

It is intended to arrange plane elements in front of components which reflect electromagnetic waves in the radar wave bands, in order to provide absorption or reduce reflection. <??>To this end, electrically and/or magnetically conductive materials are embedded in a material which is not an electrical conductor in order to form conductive regions. The dimensions of the conductive regions are at least 1000 times smaller, in all planes, than the wavelength of the waves to be absorbed, the electrically and/or magnetically conductive materials making up to 40% of the weight of the plane element.

Description

Die Erfindung bezieht sich auf einen Fassadenaufbau von Hochbauten, wie Gebäuden, insbesondere im Dünnschicht­aufbau, wobei die Außenbereiche durch Flächenelemente gebildet sind.The invention relates to a facade structure of high-rise buildings, such as buildings, in particular in thin-layer construction, the outer regions being formed by surface elements.

Derartige Ausbildungen sind bekannt und dienen als Fassadenverkleidungen zusätzlich zum Witterungsschutz als ästhetische Elemente der Gebäude. Es hat sich aber gezeigt, daß durch große geometrische Abmessungen der Gebäude und damit entstehende großflächige ebene Konturen, insbesondere unter Verwendung von elektrisch leitenden oder magnetischen Werkstoffen, Probleme entstehen, wenn derartige Bauwerke in unmittelbarer Nähe von Richtfunkstrecken und Flugsicherungsanlagen (Airport Surveillance Radar) angeordnet sind. In diesen Fällen werden durch die Gebäude Reflexionen geschaffen, die beispielsweise mit den Flugzeug-Transpondern Fehlmeldungen in Bereichen bis zu 100 km erzeugen.Such designs are known and serve as facade cladding in addition to weather protection as aesthetic elements of the building. However, it has been shown that large geometric dimensions of the buildings and the resulting large-scale flat contours, in particular using electrically conductive or magnetic materials, cause problems if such structures are arranged in the immediate vicinity of radio relay links and air traffic control systems (airport surveillance radar) . In these cases, the buildings create reflections, which, for example, use the aircraft transponders to generate incorrect messages in ranges up to 100 km.

Die Aufgabe der Erfindung ist es, einen Fassadenaufbau der gattungsgemäßen Art zu schaffen, der auf einfache Weise eine Reflexionsdämpfung bzw. Absorption der auftretenden elektromagnetischen Wellen ermöglicht und damit eine Beeinträchtigung von Richtfunkstrecken und ASR-Anlagen vermeidet.The object of the invention is to provide a facade structure of the generic type that allows reflection damping or absorption of the electromagnetic waves that occur in a simple manner and thus avoids interference with directional radio links and ASR systems.

Die Lösung dieser Aufgabe erfolgt erfindungsgemäß dadurch, daß im Außenbereich vor elektromagnetischen Wellen reflektierenden Bauteilen Beschichtungen aus absorbierendem Material für die elektromagnetischen Wellen angeordnet sind, das aus einem elektrischen Nichtleiter besteht, in das elektrisch leitfähige und/oder magnetische Materialien zur Bildung von Leitfähigkeitsbereichen eingelagert sind, deren Abmes­sungen in allen Ebenen mindestens 1000-fach geringer als die Wellenlänge der zu absorbierenden elektro­magnetischen Wellen sind und die elektrisch leitfähige und/oder magnetische Materialien bis zu 40 % des Gewichts der Beschichtung ausmachen.This object is achieved according to the invention in that coatings of absorbent material for the electromagnetic waves are arranged in the outer region in front of components reflecting electromagnetic waves, said material consisting of an electrical non-conductor, in which electrically conductive and / or magnetic materials for forming conductivity regions are embedded, whose dimensions in all levels are at least 1000 times less than the wavelength of the electromagnetic waves to be absorbed and the electrically conductive and / or magnetic materials make up up to 40% of the weight of the coating.

Durch diese Ausbildung werden die auftreffenden Wellen durch die gebildeten Leitfähigkeitsbereiche im wesent­lichen absorbiert bzw. gedämpft, indem die enthaltene Energie in Wärme umgewandelt wird.As a result of this configuration, the impinging waves are essentially absorbed or damped by the conductivity regions formed, in that the energy contained is converted into heat.

Eine vorteilhafte Ausbildung wird dadurch geschaffen, daß die Flächenelemente durch einen Kunststoff als elektrischer Nichtleiter gebildet und eingelagerte Rußpartikel als elektrisch leitfähiges Material ange­ordnet sind.An advantageous embodiment is created in that the surface elements are formed by a plastic as an electrical non-conductor and soot particles are arranged as an electrically conductive material.

Weiterhin wird vorgeschlagen, daß als magnetisches Material Carbonyleisenpulver einsetzbar ist.It is further proposed that carbonyl iron powder can be used as the magnetic material.

Zur weiteren Verbesserung der erfindungsgemäßen Aus­bildung wird vorgeschlagen, daß die Flächen, an denen die elektromagnetischen Wellen reflektieren, derart strukturiert ist, daß durch unterschiedliche Laufzeiten der reflektierten elektromagnetischen Wellenanteile eine Subtraktion durchführbar ist.To further improve the design according to the invention, it is proposed that the surfaces on which the electromagnetic waves reflect are structured in such a way that subtraction can be carried out by different transit times of the reflected electromagnetic wave components.

Eine spezielle Ausbildung besteht darin, daß die Flächen, an denen die elektromagnetischen Wellen reflektieren, eine Tiefenstruktur, wie eine genutete Oberfläche, aufweisen.A special design is that the surfaces on which the electromagnetic waves reflect have a deep structure, such as a grooved surface.

Ferner ist vorgesehen, daß die Beschichtung aus mehre­ren Schichten gebildet ist und die elektrisch leit­fähigen und/oder magnetischen Materialien unterschied­liche Gewichtsteile aufweisen. Zur Verbesserung ist zusätzlich vorgesehen, daß vor der besichtung ein metallisches Gitter als Antenne zur Reflexion angeord­net ist und durch unterschiedliche Laufzeiten der reflektierenden elektromagnetischen Wellenanteile eine Subtraktion durchführbar ist.It is further provided that the coating is formed from several layers and the electrically conductive and / or magnetic materials have different parts by weight. For improvement, it is additionally provided that a metallic grating is arranged as an antenna for reflection before the inspection and that a subtraction can be carried out by different transit times of the reflecting electromagnetic wave components.

Durch diesen erfindungsgemäßen Aufbau ist es möglich, die Probleme der störenden Reflexion von Hochbauten auszuschalten. Die Flächenelemente mit Beschichtungen werden entsprechend dem vorgeschlagenen Aufbau üb­licherweise am Baukörper befestigt, wobei Schutzschich­ten aus elektrischen Nichtleitern zusätzlich aufge­bracht bzw. vorgeschaltet werden können, um eine aus einem anderen Werkstoff gebildete Fassadenaußenseite zu bilden. Die in die Flächenelemente eingebrachten elektrisch leitfähigen und/oder magnetischen Materia­lien werden als Verluststoffe in elektrisch nichtleitende Materialien eingebracht. Dieses kann gegebenenfalls im Herstellungsverfahren erfolgen. Hierbei wird eine Bemessung von Leitfähigkeitsbereichen entsprechend der Wellenlänge der zu absorbierenden Wellen durchgeführt.This construction according to the invention makes it possible to eliminate the problems of the disturbing reflection of high-rise buildings. The surface elements with coatings are usually fastened to the structure in accordance with the proposed structure, protective layers made of electrical non-conductors being additionally able to be applied or connected upstream in order to form a facade exterior formed from a different material. The electrically conductive and / or magnetic materials introduced into the surface elements are transformed into electrical waste materials introduced non-conductive materials. This can optionally be done in the manufacturing process. Here, conductivity areas are dimensioned according to the wavelength of the waves to be absorbed.

Die Beschichtung kann durch Flammspritzen/Plasma­spritzen aufgebracht werden. Alternativ kann selbstver­ständlich der Aufbau mehrerer Teilschichten durch Walzplattieren erfolgen.The coating can be applied by flame spraying / plasma spraying. Alternatively, of course, several partial layers can be built up by roll cladding.

Claims (7)

1. Fassadenaufbau von Hochbauten, wie Gebäuden, insbesondere im Dünnschichtaufbau, wobei die Außenbereiche durch Flächenelemente gebildet sind, dadurch gekennzeichnet, daß im Außenbereich vor elektromagnetischen Wellen reflektierenden Bau­teilen Beschichtungen aus absorbierendem Material für die elektromagnetischen Wellen angebracht sind, das aus einem elektrischen Nichtleiter besteht, in das elektrisch leitfähige und/oder magnetische Materialien zur Bildung von Leitfähigkeitsbereichen eingelagert sind, deren Abmessungen in allen Ebenen mindestens 1000-fach geringer als die Wellenlänge der zu absorbierenden elektromagnetischen Wellen sind und die elektrisch leitfähige und/oder magne­tische Materialien bis zu 40 % der Beschichtung ausmachen.1. Facade construction of high-rise buildings, such as buildings, in particular in thin-layer construction, the outer regions being formed by surface elements, characterized in that coatings of absorbing material for the electromagnetic waves, which consists of an electrical non-conductor, are applied in the outer region in front of components reflecting electromagnetic waves. in which electrically conductive and / or magnetic materials are embedded to form conductivity areas, the dimensions of which are at least 1000 times smaller in all planes than the wavelength of the electromagnetic waves to be absorbed and the electrically conductive and / or magnetic materials up to 40% of the coating turn off. 2. Fassadenaufbau nach Anspruch 1, dadurch gekenn­zeichnet, daß die Flächenelemente durch einen Kunststoff als elektrischer Nichtleiter gebildet und eingelagerte Rußpartikel als elektrisch leit­fähiges Material angeordnet sind.2. Facade structure according to claim 1, characterized in that the surface elements are formed by a plastic as an electrical non-conductor and embedded soot particles are arranged as an electrically conductive material. 3. Fassadenaufbau nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß als magnetisches Material Carbonyleisenpulver einsetzbar ist.3. Facade structure according to claim 1 or 2, characterized in that carbonyl iron powder can be used as the magnetic material. 4. Fassadenaufbau nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Flächen, an denen die elektromagnetischen Wellen refektieren, derart strukturiert sind, daß durch unterschiedliche Laufzeiten der reflektierten elektromagnetischen Wellenanteile eine Subtraktion durchführbar ist.4. Facade structure according to one of claims 1 to 3, characterized in that the surfaces on which the electromagnetic waves refect are structured such that a subtraction can be carried out by different transit times of the reflected electromagnetic wave components. 5. Fassadenaufbau nach Anspruch 4, dadurch gekenn­zeichnet, daß die Flächen, an denen die elektro­magnetischen Wellen reflektieren, eine Tiefenstruk­tur, wie eine genutete Oberfläche, aufweisen.5. Facade structure according to claim 4, characterized in that the surfaces on which the electromagnetic waves reflect have a deep structure, such as a grooved surface. 6. Fassadenaufbau nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß die Beschichtung aus mehreren Schichten gebildet ist und die elektrisch leitfähigen und/oder magnetischen Materialien unterschiedliche Gewichtsanteile aufweisen.6. Facade structure according to one of claims 1 to 5, characterized in that the coating is formed from several layers and the electrically conductive and / or magnetic materials have different proportions by weight. 7. Fassadenaufbau nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß vor der Beschichtung ein metallisches Gitter als Antenne zur Reflexion angeordnet ist und durch unterschiedliche Lauf­zeiten der reflektierten elektromagnetischen Wellenanteile eine Subtraktion durchführbar ist.7. Facade structure according to one of claims 1 to 6, characterized in that a metallic grating is arranged as an antenna for reflection before the coating and a subtraction can be carried out by different transit times of the reflected electromagnetic wave components.
EP89123647A 1989-01-13 1989-12-21 Plane elements for the absorption or reduction of the reflection of electromagnetic waves Withdrawn EP0377879A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3900856A DE3900856A1 (en) 1989-01-13 1989-01-13 FACADE CONSTRUCTION OF BUILDINGS
DE3900856 1989-01-13

Publications (1)

Publication Number Publication Date
EP0377879A1 true EP0377879A1 (en) 1990-07-18

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EP89123647A Withdrawn EP0377879A1 (en) 1989-01-13 1989-12-21 Plane elements for the absorption or reduction of the reflection of electromagnetic waves

Country Status (4)

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US (1) US5084705A (en)
EP (1) EP0377879A1 (en)
JP (1) JPH02232997A (en)
DE (1) DE3900856A1 (en)

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JPH04145992A (en) * 1990-10-08 1992-05-19 Ryoko Sangyo Kk Floor material and wall material for preventing static electricity and shielding electromagnetic wave formed by utilizing waste
DE4035460A1 (en) * 1990-11-08 1992-05-14 Messerschmitt Boelkow Blohm Large surface, sandwiched sound insulating wall - has extra material layer on side exposed to impingement for narrow band suppression
JPH04316996A (en) * 1991-04-16 1992-11-09 Mitsubishi Heavy Ind Ltd Radar reflection reducing device for aircraft and the like
JPH04354103A (en) * 1991-05-31 1992-12-08 Yoshiyuki Naito Wideband radio wave absorbing device
US5353029A (en) * 1993-05-17 1994-10-04 Johnston Beverly R Separable electromagnetic waveguide attenuator
DE29703725U1 (en) * 1997-03-01 1997-04-24 EMC Testhaus Schwerte GmbH, 58239 Schwerte Area element to limit RF reflections
JP2007096269A (en) * 2005-08-30 2007-04-12 Nisca Corp Near field electromagnetic wave absorber
GB2480064A (en) * 2010-05-04 2011-11-09 Vestas Wind Sys As RAM panel arrangements for a wind turbine tower

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US3754255A (en) * 1971-04-05 1973-08-21 Tokyo Inst Tech Wide band flexible wave absorber
EP0043040A1 (en) * 1980-07-01 1982-01-06 Bayer Ag Compound material for screening against electro-magnetic radiation
EP0121655A2 (en) * 1983-03-01 1984-10-17 Dornier Gmbh Fibre composite
WO1985002265A1 (en) * 1983-11-07 1985-05-23 The Dow Chemical Company Low density, electromagnetic radiation absorption composition

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3754255A (en) * 1971-04-05 1973-08-21 Tokyo Inst Tech Wide band flexible wave absorber
EP0043040A1 (en) * 1980-07-01 1982-01-06 Bayer Ag Compound material for screening against electro-magnetic radiation
EP0121655A2 (en) * 1983-03-01 1984-10-17 Dornier Gmbh Fibre composite
WO1985002265A1 (en) * 1983-11-07 1985-05-23 The Dow Chemical Company Low density, electromagnetic radiation absorption composition

Non-Patent Citations (2)

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Title
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PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 178 (E-330)[1901], 23. Juli 1985; & JP-A-60 50 902 (TAKASE SENKOUJIYOU K.K.) 22-03-1985 *

Also Published As

Publication number Publication date
DE3900856A1 (en) 1990-07-26
US5084705A (en) 1992-01-28
JPH02232997A (en) 1990-09-14

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