EP0903806A2 - Quasi-optical filter and antenna arrangement with such a filter - Google Patents

Quasi-optical filter and antenna arrangement with such a filter Download PDF

Info

Publication number
EP0903806A2
EP0903806A2 EP98113850A EP98113850A EP0903806A2 EP 0903806 A2 EP0903806 A2 EP 0903806A2 EP 98113850 A EP98113850 A EP 98113850A EP 98113850 A EP98113850 A EP 98113850A EP 0903806 A2 EP0903806 A2 EP 0903806A2
Authority
EP
European Patent Office
Prior art keywords
filter
energy
filter according
frequency
layers
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Withdrawn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
EP98113850A
Other languages
German (de)
French (fr)
Other versions
EP0903806A3 (en
Inventor
Gerhard Friedsam
Ralph Rasshofer
Erwin Dr. Biebl
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.)
Spinner GmbH
Original Assignee
Spinner GmbH
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 Spinner GmbH filed Critical Spinner GmbH
Publication of EP0903806A2 publication Critical patent/EP0903806A2/en
Publication of EP0903806A3 publication Critical patent/EP0903806A3/en
Withdrawn legal-status Critical Current

Links

Images

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
    • H01Q17/001—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems for modifying the directional characteristic of an aerial
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/14—Reflecting surfaces; Equivalent structures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/23—Combinations of reflecting surfaces with refracting or diffracting devices
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
    • H01Q19/06—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens
    • H01Q19/08—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens for modifying the radiation pattern of a radiating horn in which it is located

Definitions

  • the invention relates to a quasi-optical filter for division of themselves under open space conditions with different Frequencies spreading RF energy, consisting of a filter plate with a number of layers of fabrics, their dielectric numbers and their thicknesses selected in this way are that the filter for RF energy of a first frequency the highest possible transmission factor and for RF energy at least one second frequency has a high reflection factor Has.
  • DE 36 01 553 C2 describes an arrangement for division of RF energy known to be essentially the same as the above has the specified structure.
  • This arrangement serves as at least Parabolic antenna for RF energy to be reflected a "second" frequency over one of the usual feed arrangements is shed.
  • the RF energy of a "first" Frequency which is an odd fraction of the second Frequency is from a separate antenna system that either behind the parabolic antenna or in this is integrated, emitted.
  • the The first frequency is that which forms the parabolic antenna Arrangement permeable, so that the main beam direction of the RF energy the first frequency with that of the second Frequency coincides.
  • the invention is based on another problem, however is that oscillators regularly in addition to the RF energy the desired frequency also RF energy at harmonic frequencies produce. Especially with microwave and Millimeter oscillators above about 10 GHz is the one at the first and often still the second harmonic RF energy is slightly less than the RF energy of the Fundamental wave. To suppress the RF energy on the unwanted Harmonic frequencies are therefore regular Harmonic filter with a high blocking attenuation of typical more than 30 dB necessary.
  • the invention has for its object a related Filter that can be used with the radiation of RF energy to suppress harmonics, at least the first Harmonic to create that regardless of the presence a waveguide connection between the RF energy source and the antenna is.
  • the invention is based on that known, quasi-optical filter according to the preamble of claim 1 and proposes the dielectric constant and to measure the thickness of the layers so that the second frequency is a multiple of the first frequency.
  • the dimensions of the filter perpendicular to its thickness should be greater than four wavelengths of RF energy be the first frequency (claim 2). The larger these dimensions the smaller the divergence of the RF energy beam. When attaching the filter at the waist one Gaussian beam, however, the four wavelengths mentioned are sufficient the RF energy of the first frequency.
  • the filter consists of flat layers.
  • the surfaces can be used to adapt to curved wavefronts of the layers but also cutouts of the surfaces of spheres with a common center (claim 3) or of ellipsoids with common focal points (claim 4) be.
  • the filter can be an integral part of the lens form (claim 8).
  • the filter can be on a the large areas of the dielectric lens arranged and with this be connected in one piece.
  • the harmonics are reflected on the filter.
  • a flat filter whose surface normal with the main beam direction of the RF energy coincides, that is Harmonics reflected back into the signal source. This is often undesirable and can be avoided if the surface normal of the filter with the main beam direction of the RF energy encloses an angle (claim 9). That angle can e.g. be between 10 ° and 60 °.
  • an absorber for the reflected RF energy is attached be (claim 10).
  • the proposed quasi-optical filter is preferred Suppression of at least the first harmonic of an RF signal used (claim 11).
  • Figure 1 shows a harmonic filter of seven layers, from which four layers 1 have a first thickness d1, between which are three layers 2 with the thickness d2.
  • the dielectric numbers and the thicknesses d1, d2 of the layers 1, 2 are dimensioned so that the filter for one of its large areas e.g. RF radiation striking in the direction of arrow P. a given usable frequency as high as possible Has a transmission factor, but at least that in the HF radiation first harmonic also contained accordingly reflected twice the useful frequency as completely as possible.
  • the layers 1, 2 forming Materials very different dielectric numbers and possibly also very different relative Have permitivities.
  • the filter is only two different embodiments Layered fabrics.
  • the filter can be used as a flat circular disc be trained. In this case the diameter is D at least four times the wavelength of the fundamental wave according to the useful frequency.
  • the useful frequency is preferably in the gigahertz range.
  • While the filter of Figure 1 is mainly used as a harmonic filter for HF radiation with at least approximately 2 shows an embodiment for HF radiation with curved, e.g. spherically curved Wave fronts.
  • the harmonic filter is analog that constructed according to FIG. 1. It also consists of only two different substances, namely two layers 21 and three layers 22. Layers 21, 22 Cutouts from the surfaces of spheres with a common Center.
  • Figure 3 shows a flat filter with four equal layers 31, which are separated from one another by spacers 33.
  • the thickness of the spacers 33 defines the thickness d2 of the layers 32, which here consist of air, but also of can be a plastic foam, the dielectric constant is very close to one.
  • FIG. 4 shows a flat filter plate 4 with a similar one Structure as shown in Fig. 1, but on the large area a dielectric lens 5 arranged and with this in appropriately connected.
  • the dielectric lens 5 serves as usual the beam shaping of those passing through the filter 4 HF radiation with the useful frequency.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Aerials With Secondary Devices (AREA)

Abstract

The individual layers comprise different dielectric and/or magnetic properties. The filter plate is located in a signal path of a HF transmission path at a point, at which the HF signal is not passed through a waveguide. The thickness, permittivity, and permeability of the individual layers are so chosen that the signal wave passes through the filter plate almost unattenuated, while at least the first, but possibly also further harmonics are reflected. The dimensions of the filter plate, except the thickness, are more than four wavelength of the signal wave by propagation through air.

Description

Die Erfindung betrifft ein quasioptisches Filter zur Aufteilung von sich unter Freiraumbedingungen mit unterschiedlichen Frequenzen ausbreitender HF-Energie, bestehend aus einer Filterplatte mit einer Anzahl von Schichten aus Stoffen, deren Dielektrizitätszahlen und deren Dicken so gewählt sind, daß das Filter für HF-Energie einer ersten Frequenz einen möglichst hohen Transmissionsfaktor und für HF-Energie mindestens einer zweiten Frequenz einen hohen Reflexionsfaktor hat.The invention relates to a quasi-optical filter for division of themselves under open space conditions with different Frequencies spreading RF energy, consisting of a filter plate with a number of layers of fabrics, their dielectric numbers and their thicknesses selected in this way are that the filter for RF energy of a first frequency the highest possible transmission factor and for RF energy at least one second frequency has a high reflection factor Has.

Aus der DE 36 01 553 C2 ist eine Anordnung zur Aufteilung von HF-Energie bekannt, die im wesentlichen den vorstehend angegebenen Aufbau hat. Diese Anordnung dient als zumindest parabolähnliche Antenne für zu reflektierende HF-Energie einer "zweiten" Frequenz, die über eine der üblichen Speiseanordnungen abgestralt wird. Die HF-Energie einer "ersten" Frequenz, die ein ungeradzahliger Bruchteil der zweiten Frequenz ist, wird von einem getrennten Antennensystem, das entweder hinter der parabolähnlichen Antenne liegt oder in diese integriert ist, abgestrahlt. Für diese HF-Energie der ersten Frequenz ist die die parabolähnliche Antenne bildende Anordung durchlässig, so daß die Hauptstrahlrichtung der HF-Energie der ersten Frequenz mit derjenigen der zweiten Frequenz zusammenfällt.DE 36 01 553 C2 describes an arrangement for division of RF energy known to be essentially the same as the above has the specified structure. This arrangement serves as at least Parabolic antenna for RF energy to be reflected a "second" frequency over one of the usual feed arrangements is shed. The RF energy of a "first" Frequency which is an odd fraction of the second Frequency is from a separate antenna system that either behind the parabolic antenna or in this is integrated, emitted. For this RF energy the The first frequency is that which forms the parabolic antenna Arrangement permeable, so that the main beam direction of the RF energy the first frequency with that of the second Frequency coincides.

Eine ähnliche Verwendung einer solchen quasioptischen Filteranordnung im wesentlichen als Reflektor ist aus der DE 196 07 934 C1 bekannt. Das Filter reflektiert den frequenzmäßig erwünschten Anteil der einfallenden HF-Energie, während die frequenzmäßig unerwünschten Anteile in den Reflektoraufbau, also das Filter, ein- und aus diesem rückseitig wieder austreten sollen. Allerdings ist der Reflektor nicht vollständig transparent. Aus Figur 2 der Schrift ergibt sich, daß z.B. die erwünschten, reflektierten Anteile der HF-Energie bei ca. 10 und ca. 13,5 GHz liegen, während die unerwünschten Anteile bei ca. 11,5 und 14,5 GHz liegen.A similar use of such a quasi-optical filter arrangement essentially as a reflector is from DE 196 07 934 C1 known. The filter reflects the frequency desired portion of the incident RF energy while the frequency-undesirable components in the reflector structure, So the filter, in and out of this on the back to exit again. However, the reflector is not completely transparent. From Figure 2 of the script results that e.g. the desired, reflected portions of the RF energy is around 10 and around 13.5 GHz, while the undesirable components are around 11.5 and 14.5 GHz.

Die Erfindung geht jedoch von einem anderen Problem aus, das darin besteht, daß Oszillatoren regelmäßig neben der HF-Energie der gewünschten Frequenz auch HF-Energie auf Oberwellenfrequenzen erzeugen. Insbesondere bei Mikrowellen- und Millimeter-Oszillatoren oberhalb von etwa 10 GHz ist die bei der ersten und oft noch der zweiten Oberwelle ab gegebene HF-Energie unwesentlich geringer als die HF-Energie der Grundwelle. Zur Unterdrückung der HF-Energie auf den unerwünschten Oberwellenfrequenzen sind daher regelmäßig Oberwellenfilter mit einer hohen Sperrdämpfung von typisch mehr als 30 dB notwendig.The invention is based on another problem, however is that oscillators regularly in addition to the RF energy the desired frequency also RF energy at harmonic frequencies produce. Especially with microwave and Millimeter oscillators above about 10 GHz is the one at the first and often still the second harmonic RF energy is slightly less than the RF energy of the Fundamental wave. To suppress the RF energy on the unwanted Harmonic frequencies are therefore regular Harmonic filter with a high blocking attenuation of typical more than 30 dB necessary.

Bekannte Lösungen sehen das Oberwellenfilter in dem die Signalquelle und die Sendeantenne verbindenden Wellenleiter vor, vgl. zB. H. S. Wa, M. Tsuji, "A Completely Theoretical Design Method of Dielectric Image Guide Gratings in the Bragg Reflection Region", IEEE Transactions on Microwave and Techniques, Band MTT-34, Nr. 4, April 1986 und J.J. Taub, J. Cohen, "Quasi-optical Waveguide Filter for Millimeter and Submillimeter Wavelengths", Proceedings of the IEEE, Band 54, Nr. 4, April 1966. Die Verwirklichung solcher gleichzeitig als Oberwellenfilter wirkender Wellenleiter ist allerdings konstruktiv sehr aufwendig, bei Hohlleitern sogar prinzipbedingt unmöglich. Hinzu kommt, daß das Prinzip bei Oszillatoren, die mit der Antennne nicht über einen Wellenleiter verbunden sondern in diese integriert sind, nicht anwendbar ist.Known solutions see the harmonic filter in which the Signal source and the waveguide connecting the transmitting antenna before, cf. e.g. H. S. Wa, M. Tsuji, "A Completely Theoretical Design Method of Dielectric Image Guide Gratings in the Bragg Reflection Region ", IEEE Transactions on Microwave and Techniques, Volume MTT-34, No. 4, April 1986 and J.J. Taub, J. Cohen, "Quasi-Optical Waveguide Filters for Millimeters and Submillimeter Wavelengths ", Proceedings of the IEEE, volume 54, No. 4, April 1966. The realization of such at the same time however, is a waveguide acting as a harmonic filter structurally very complex, even with waveguides in principle impossible. In addition, the principle at Oscillators connected to the antenna do not have a waveguide connected but not integrated into it is applicable.

Allerdings ist auch schon ein quasioptisches Bandpaßfilter bekannt, das direkt in den Strahlengang einer hochfrequenten Übertragungsstrecke außerhalb eines Wellenleiters eingebracht werden kann (siehe z.B. P.G. Wannier, J.A. Arnaud, F.A. Pelow, A.A.M. Saleh, "Quasioptical Band-Rejection Filter at 100 GHz", Rev. Sci. Instrum., Band 47, Nr. 1, Januar 1976). Das Filter besteht aus einer planparallelen dielektrischen Scheibe die beidseitig mit periodischen, planaren, metallischen Streukörpern strukturiert ist. Auf diese Weise arbeitet das Filter nach dem Prinzip des in der Lasertechnik üblichen Fabry-Perrot-Resonators. Allerdings ist dieses Filter schmalbandig, hat eine verhältnismäßig hohe Einfügedämpfung von 2 bis 3 dB im Durchlaßbereich und eine unzureichende Sperrdämpfung.However, there is also a quasi-optical bandpass filter known that directly into the beam path of a high frequency Transmission path introduced outside a waveguide (see e.g. P.G. Wannier, J.A. Arnaud, FA. Pelow, A.A.M. Saleh, "Quasi-Optical Band Rejection Filter at 100 GHz ", Rev. Sci. Instrum., Volume 47, No. 1, January 1976). The filter consists of a plane parallel dielectric disc with periodic, planar, metallic scattering bodies is structured. On this way the filter works on the principle of in the Laser technology usual Fabry-Perrot resonators. Indeed if this filter is narrow-band, it has a relative high insertion loss of 2 to 3 dB in the pass band and inadequate barrier damping.

Der Erfindung liegt die Aufgabe zugrunde, ein im Zusammenhang mit der Abstrahlung von HF-Energie verwendbares Filter zur Unterdrückung von Oberwellen, mindestens der ersten Oberwelle, zu schaffen, das unabhängig von dem Vorhandensein einer Wellenleiterverbindung zwischen der HF-Energiequelle und der Antenne ist.The invention has for its object a related Filter that can be used with the radiation of RF energy to suppress harmonics, at least the first Harmonic to create that regardless of the presence a waveguide connection between the RF energy source and the antenna is.

Zur Lösung dieser Aufgabe geht die Erfindung von dem an sich bekannten, quasioptischen Filter gemäß dem Oberbegriff des Anspruches 1 aus und schlägt vor, die Dielektrizitätszahlen und die Dicken der Schichten so zu bemessen, daß die zweite Frequenz ein Vielfaches der ersten Frequenz ist.To achieve this object, the invention is based on that known, quasi-optical filter according to the preamble of claim 1 and proposes the dielectric constant and to measure the thickness of the layers so that the second frequency is a multiple of the first frequency.

Die Filtercharakteristik kann durch die Wahl der Dielektrizitätszahl εr sowie die Dicke der einzelnen Schichten eingestellt werden. Sofern die die einzelnen Schichten bildenden Stoffe auch eine von 1 verschiedene relative Permeabilität µr haben, ist auch diese zu berücksichtigen. Bekanntlich wird eine maximale Sperrdämpfung dann erreicht, wenn die Dicke h jeder Schicht gleich λ/4 ist, wobei λ=λ0/√εrµr die Wellenlänge in dem gewünschten Stoff bei der gewünschten Sperrfrequenz ist. Durch kleine Abweichungen der Schichtdicken von dem genannten Wert kann jedoch der Sperrbereich verbreitert oder die Welligkeit im Durchlaßbereich reduziert werden. Bei geeigneter Wahl der Schichten lassen sich die Mitte des Sperrbereichs und dessen Breite so einstellen, daß neben der ersten auch höhere Oberwellen noch in den Sperrbereich fallen.The filter characteristic can be set by choosing the dielectric constant ε r and the thickness of the individual layers. If the substances forming the individual layers also have a relative permeability µ r different from 1, this must also be taken into account. As is known, a maximum blocking attenuation is achieved when the thickness h of each layer is equal to λ / 4, where λ = λ 0 / √ε r µ r is the wavelength in the desired substance at the desired blocking frequency. By small deviations of the layer thicknesses from the mentioned value, however, the blocking area can be widened or the ripple in the pass band can be reduced. With a suitable choice of the layers, the center of the blocking area and its width can be adjusted so that in addition to the first, higher harmonics also fall into the blocking area.

Die Abmessungen des Filters rechtwinklig zu seiner Dicke sollten größer als vier Wellenlängen der HF-Energie der ersten Frequenz sein (Anspruch 2). Je größer diese Abmessungen sind, desto kleiner ist die Divergenz des HF-Energiestrahls. Bei Anbringung des Filters in der Taille eines Gauß'schen Strahls reichen jedoch die genannten vier Wellenlängen der HF-Energie der ersten Frequenz aus.The dimensions of the filter perpendicular to its thickness should be greater than four wavelengths of RF energy be the first frequency (claim 2). The larger these dimensions the smaller the divergence of the RF energy beam. When attaching the filter at the waist one Gaussian beam, however, the four wavelengths mentioned are sufficient the RF energy of the first frequency.

Im einfachsten Fall besteht das Filter aus planen Schichten. Zur Anpassung an gekrümmte Wellenfronten können die Oberflächen der Schichten jedoch auch Ausschnitte der Oberflächen von Kugeln mit einem gemeinsamen Mittelpunkt (Anspruch 3) oder von Ellipsoiden mit gemeinsamen Brennpunkten (Anspruch 4) sein.In the simplest case, the filter consists of flat layers. The surfaces can be used to adapt to curved wavefronts of the layers but also cutouts of the surfaces of spheres with a common center (claim 3) or of ellipsoids with common focal points (claim 4) be.

Es ist bekannt, daß die Filterwirkung quasioptischer Filter umso besser ist, je größer der Unterschied zwischen der relativen Dielektrizitätszahlen (und gegebenenfalls den relativen Permeabilitäten) der Stoffe aufeinanderfolgender Schichten ist. Hierzu kann zum Beispiel mindestens einer der Stoffe der Schichten ein Gas (Anspruch 5) oder ein Kunststoffschaum (Anspruch 6) sein. Zumindest im ersteren Fall wird die Dicke der betreffenden Schicht durch entsprechende Abstandshalter festgelegt.It is known that the filter effect of quasi-optical filters the better the bigger the difference between the relative dielectric constant (and possibly the relative permeabilities) of the substances in succession Layers is. For example, at least one of the Materials of the layers a gas (claim 5) or a plastic foam (Claim 6). At least in the former case is the thickness of the layer concerned by appropriate Spacers set.

Wenn die HF-Energie über eine Hornantenne abgestrahlt wird, kann das Filter gleichzeitig als Abdeckung der strahlenden Öffnung dieser Sonderform eines Hohlleiters ausgebildet sein (Anspruch 7). When the RF energy is radiated through a horn antenna, can be used as a cover for the radiating filter Opening of this special form of a waveguide can be formed (Claim 7).

Häufig werden in Verbindung mit Höchstfrequenzantennen dielektrische Linsen zur Strahlformung eingesetzt. In diesem Fall kann das Filter einen integralen Bestandteil der Linse bilden (Anspruch 8). Insbesondere kann das Filter auf einer der Großflächen der dielektrischen Linse angeordnet und mit dieser einstückig verbunden sein.Dielectric is often used in conjunction with high-frequency antennas Lenses used for beam shaping. In this Case, the filter can be an integral part of the lens form (claim 8). In particular, the filter can be on a the large areas of the dielectric lens arranged and with this be connected in one piece.

Die Oberwellen werden an dem Filter reflektiert. Im Fall eines ebenen Filters, dessen Flächennormale mit der Hauptstrahlrichtung der HF-Energie zusammenfällt, werden also die Oberwellen in die Signalquelle zurückreflektiert. Dies ist häufig unerwünscht und kann vermieden werden wenn die Flächennormale des Filters mit der Hauptstrahlrichtung der HF-Energie einen Winkel einschließt (Anspruch 9). Dieser Winkel kann z.B. zwischen 10° und 60° betragen.The harmonics are reflected on the filter. In the case a flat filter, whose surface normal with the main beam direction of the RF energy coincides, that is Harmonics reflected back into the signal source. This is often undesirable and can be avoided if the surface normal of the filter with the main beam direction of the RF energy encloses an angle (claim 9). That angle can e.g. be between 10 ° and 60 °.

Bei einer Antennenanordnung, die ein so orientiertes Filter umfaßt, kann in Fortpflanzungsrichtung der reflektierten HF-Energie der zweiten Frequenz außerhalb der Hauptstrahlrichtung ein Absorber für die reflektierte HF-Energie angebracht sein (Anspruch 10).In the case of an antenna arrangement which has such a oriented filter includes, can in the direction of propagation of the reflected RF energy the second frequency outside the main beam direction an absorber for the reflected RF energy is attached be (claim 10).

Bevorzugt wird das vorgeschlagene, quasioptische Filter zur Unterdrückung mindestens der ersten Oberwelle eines HF-Signals verwendet (Anspruch 11).The proposed quasi-optical filter is preferred Suppression of at least the first harmonic of an RF signal used (claim 11).

In der Zeichnung ist das quasioptische Filter nach der Erfindung in mehreren, beispielsweise gewählten Ausführungsformen schematisch vereinfacht im Schnitt dargestellt. Es zeigt:

Fig. 1
ein planes Filter,
Fig. 2
eine besonders einfache Ausführungsform eines planen Filters,
Fig. 3
ein halbkugelförmiges Filter,
Fig. 4
ein planes Filter in Verbindung mit einer dielektrischen Linse.
In the drawing, the quasi-optical filter according to the invention is shown schematically in simplified form in several, for example selected, embodiments in section. It shows:
Fig. 1
a flat filter,
Fig. 2
a particularly simple embodiment of a flat filter,
Fig. 3
a hemispherical filter,
Fig. 4
a flat filter in conjunction with a dielectric lens.

Figur 1 zeigt ein Oberwellenfilter aus sieben Schichten, von denen vier Schichten 1 eine erste Dicke d1 haben, zwischen denen drei Schichten 2 mit der Dicke d2 liegen. Die Dielektrizitätszahlen und die Dicken d1, d2 der Schichten 1, 2 sind so bemessen, daß das Filter für auf eine seiner Großflächen z.B. in Richtung des Pfeiles P auffallende HF-Strahlung einer gegebenen Nutzfrequenz einen möglichst hohen Transmissionsfaktor hat, jedoch mindestens die in der HF-Strahlung ebenfalls enthaltene erste Oberwelle entsprechend dem Doppelten der Nutzfrequenz möglichst vollständig reflektiert. Es ist zweckmäßig, wenn die die Schichten 1, 2 bildenden Materialien sehr unterschiedliche Dielektrizitätszahlen und gegebenenfalls auch sehr unterschiedliche relative Permitivitäten haben. In diesem nicht beschränkenden Ausführungsbeispiel ist das Filter aus nur zwei unterschiedlichen Stoffen geschichtet. Das Filter kann als plane Kreisscheibe ausgebildet sein. In diesem Fall beträgt der Durchmesser D wenigstens das Vierfache der Wellenlänge der Grundwelle entsprechend der Nutzfrequenz. Die Nutzfrequenz liegt bevorzugt im Gigahertzbereich.Figure 1 shows a harmonic filter of seven layers, from which four layers 1 have a first thickness d1, between which are three layers 2 with the thickness d2. The dielectric numbers and the thicknesses d1, d2 of the layers 1, 2 are dimensioned so that the filter for one of its large areas e.g. RF radiation striking in the direction of arrow P. a given usable frequency as high as possible Has a transmission factor, but at least that in the HF radiation first harmonic also contained accordingly reflected twice the useful frequency as completely as possible. It is expedient if the layers 1, 2 forming Materials very different dielectric numbers and possibly also very different relative Have permitivities. In this, not restrictive The filter is only two different embodiments Layered fabrics. The filter can be used as a flat circular disc be trained. In this case the diameter is D at least four times the wavelength of the fundamental wave according to the useful frequency. The useful frequency is preferably in the gigahertz range.

Während sich das Filter nach Figur 1 vor allem als Oberwellenfilter für HF-Strahlung mit wenigstens näherungsweise ebenen Wellenfronten eignet, zeigt Figur 2 eine Ausführungsform für HF-Strahlung mit gekrümmten, z.B. kugelförmig gekrümmten Wellenfronten. Das Oberwellenfilter ist analog demjenigen nach Fig. 1 aufgebaut. Es besteht ebenfalls aus nur zwei unterschiedlichen Stoffen, nämlich zwei Schichten 21 sowie drei Schichten 22. Die Schichten 21, 22 stellen Ausschnitte aus den Oberflächen von Kugeln mit einem gemeinsamen Mittelpunkt dar. While the filter of Figure 1 is mainly used as a harmonic filter for HF radiation with at least approximately 2 shows an embodiment for HF radiation with curved, e.g. spherically curved Wave fronts. The harmonic filter is analog that constructed according to FIG. 1. It also consists of only two different substances, namely two layers 21 and three layers 22. Layers 21, 22 Cutouts from the surfaces of spheres with a common Center.

Figur 3 zeigt ein planes Filter mit vier gleichen Schichten 31, die voneinander durch Abstandhalter 33 getrennt sind. Die Dicke der Abstandhalter 33 legt die Dicke d2 der Schichten 32 fest, die hier aus Luft bestehen, jedoch auch aus einem Kunststoffschaum sein können, dessen Dielektrizitätszahl sehr nahe bei Eins liegt.Figure 3 shows a flat filter with four equal layers 31, which are separated from one another by spacers 33. The thickness of the spacers 33 defines the thickness d2 of the layers 32, which here consist of air, but also of can be a plastic foam, the dielectric constant is very close to one.

Figur 4 zeigt eine plane Filterplatte 4 mit einem ähnlichen Aufbau wie in Fig. 1 dargestellt, jedoch auf der Großfläche einer dielektrischen Linse 5 angeordnet und mit dieser in geeigneter Weise verbunden. Die dielektrische Linse 5 dient wie üblich der Strahlformung der durch das Filter 4 hindurchtretenden HF-Strahlung mit der Nutzfrequenz.FIG. 4 shows a flat filter plate 4 with a similar one Structure as shown in Fig. 1, but on the large area a dielectric lens 5 arranged and with this in appropriately connected. The dielectric lens 5 serves as usual the beam shaping of those passing through the filter 4 HF radiation with the useful frequency.

Claims (11)

Quasioptisches Filter zur Aufteilung von sich unter Freiraumbedingungen mit unterschiedlicher Frequenzen ausbreitender HF-Energie, bestehend aus einer Filterplatte aus einer Anzahl von Schichten aus Stoffen, deren Dielektrizitätszahlen und deren Dicken so gewählt sind, daß das Filter für HF-Energie einer ersten Frequenz einen möglichst hohen Transmissionsfaktor und für HF-Energie mindestens einer zweiten Frequenz einen hohen Reflexionsfaktor hat, dadurch gekennzeichnet, daß die Dielektrizitätszahlen und die Dicken (d1, d2) der Schichten (1, 2) so bemessen sind, daß die zweite Frequenz ein Vielfaches der ersten Frequenz ist.Quasi-optical filter for the division of HF energy propagating under free space conditions with different frequencies, consisting of a filter plate made of a number of layers of substances, whose dielectric numbers and thicknesses are selected so that the filter for HF energy of a first frequency is as high as possible Transmission factor and for RF energy at least one second frequency has a high reflection factor, characterized in that the dielectric numbers and the thicknesses (d1, d2) of the layers (1, 2) are dimensioned such that the second frequency is a multiple of the first frequency . Filter nach Anspruch 1, dadurch gekennzeichnet, daß seine Abmessungen (D) rechtwinklig zu seiner Dicke größer als vier Wellenlängen der HF-Energie der ersten Frequenz sind.Filter according to claim 1, characterized in that its dimensions (D) perpendicular to its thickness greater than four wavelengths of the RF energy of the first Frequency are. Filter nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Oberflächen der Schichten (22, 23) Ausschnitte der Oberflächen von Kugeln mit einem gemeinsamen Mittelpunkt sind.Filter according to claim 1 or 2, characterized in that the surfaces of the layers (22, 23) cutouts the surfaces of spheres with a common center are. Filter nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Oberflächen der Schichten Ausschnitte der Oberflächen von Ellipsoiden mit gemeinsamen Brennpunkten sind.Filter according to claim 1 or 2, characterized in that the surfaces of the layers are cutouts of the Surfaces of ellipsoids with common focal points are. Filter nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß mindestens einer der Stoffe (32) der Schichten ein Gas ist.Filter according to one of claims 1 to 4, characterized in that that at least one of the substances (32) of the Stratification is a gas. Filter nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß mindestens einer der Stoffe der Schichten ein Kunststoffschaum ist.Filter according to one of claims 1 to 5, characterized in that that at least one of the substances of the Layers is a plastic foam. Filter nach einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, daß es als Abdeckung der strahlenden Öffnung eines Hohlleiters ausgebildet ist.Filter according to one of claims 1 to 6, characterized in that that it is as a cover of the radiant Opening of a waveguide is formed. Filter nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, daß es einen integralen Bestandteil (4) einer dielektrischen Linse (5) bildet.Filter according to one of claims 1 to 7, characterized in that that it is an integral part (4) a dielectric lens (5). Filter nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, daß seine Flächennormale mit der Hauptstrahlrichtung der HF-Energie einen Winkel einschließt.Filter according to one of claims 1 to 8, characterized in that that its surface normal with the main beam direction the RF energy encloses an angle. Antennenanordnung mit einem Filter nach Anspruch 9, gekennzeichnet durch einen in Fortpflanzungsrichtung der reflektierten HF-Energie der zweiten Frequenz außerhalb der Hauptstrahlrichtung angeordneten Absorber für die reflektierte HF-Energie.Antenna arrangement with a filter according to claim 9, characterized by a in the direction of reproduction the reflected RF energy of the second frequency outside the absorber arranged in the main beam direction for the reflected RF energy. Verwendung eines Filters nach einem der Ansprüche 1 bis 10 zur Unterdrückung mindestens der ersten Oberwelle eines HF-Signals.Use of a filter according to one of claims 1 to 10 to suppress at least the first harmonic of an RF signal.
EP98113850A 1997-07-29 1998-07-24 Quasi-optical filter and antenna arrangement with such a filter Withdrawn EP0903806A3 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE1997132569 DE19732569A1 (en) 1997-07-29 1997-07-29 Quasi-optical harmonic wave filter for HF signal generation
DE19732569 1997-07-29

Publications (2)

Publication Number Publication Date
EP0903806A2 true EP0903806A2 (en) 1999-03-24
EP0903806A3 EP0903806A3 (en) 1999-03-31

Family

ID=7837215

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98113850A Withdrawn EP0903806A3 (en) 1997-07-29 1998-07-24 Quasi-optical filter and antenna arrangement with such a filter

Country Status (2)

Country Link
EP (1) EP0903806A3 (en)
DE (1) DE19732569A1 (en)

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3698001A (en) * 1969-11-11 1972-10-10 Nippon Telegraph & Telephone Frequency group separation filter device using laminated dielectric slab-shaped elements
US3842421A (en) * 1973-02-15 1974-10-15 Philco Ford Corp Multiple band frequency selective reflectors
US4343002A (en) * 1980-09-08 1982-08-03 Ford Aerospace & Communications Corporation Paraboloidal reflector spatial filter
DE3601553A1 (en) * 1986-01-21 1987-07-23 Licentia Gmbh Arrangement for the distribution of extremely high frequency energy
US4864321A (en) * 1984-08-20 1989-09-05 Radant Technologies, Inc. Electromagnetic energy shield
US5455594A (en) * 1992-07-16 1995-10-03 Conductus, Inc. Internal thermal isolation layer for array antenna
US5471180A (en) * 1991-02-15 1995-11-28 Lockheed Sanders, Inc. Low-loss dielectric resonant devices having lattice structures with elongated resonant defects
US5563614A (en) * 1989-12-19 1996-10-08 Her Majesty In Right Of Canada, As Represented By The Minister Of Communications Low noise dual polarization electromagnetic power reception and conversion system
DE19607934C1 (en) * 1996-03-01 1997-07-10 Daimler Benz Aerospace Ag Reflector for two different frequency ranges

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4121584A1 (en) * 1991-06-29 1993-01-21 Messerschmitt Boelkow Blohm Camouflaging and strong elimination of radar radiation in inlet of drive - includes impinging radar radiation in inlet duct using divergent tube and associated mode converter

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3698001A (en) * 1969-11-11 1972-10-10 Nippon Telegraph & Telephone Frequency group separation filter device using laminated dielectric slab-shaped elements
US3842421A (en) * 1973-02-15 1974-10-15 Philco Ford Corp Multiple band frequency selective reflectors
US4343002A (en) * 1980-09-08 1982-08-03 Ford Aerospace & Communications Corporation Paraboloidal reflector spatial filter
US4864321A (en) * 1984-08-20 1989-09-05 Radant Technologies, Inc. Electromagnetic energy shield
DE3601553A1 (en) * 1986-01-21 1987-07-23 Licentia Gmbh Arrangement for the distribution of extremely high frequency energy
US5563614A (en) * 1989-12-19 1996-10-08 Her Majesty In Right Of Canada, As Represented By The Minister Of Communications Low noise dual polarization electromagnetic power reception and conversion system
US5471180A (en) * 1991-02-15 1995-11-28 Lockheed Sanders, Inc. Low-loss dielectric resonant devices having lattice structures with elongated resonant defects
US5455594A (en) * 1992-07-16 1995-10-03 Conductus, Inc. Internal thermal isolation layer for array antenna
DE19607934C1 (en) * 1996-03-01 1997-07-10 Daimler Benz Aerospace Ag Reflector for two different frequency ranges

Also Published As

Publication number Publication date
EP0903806A3 (en) 1999-03-31
DE19732569A1 (en) 1999-02-18

Similar Documents

Publication Publication Date Title
DE69728603T2 (en) Lens antenna with improved dielectric lens to reduce interference caused by internally reflected waves
DE60015822T2 (en) Multi-lobe antenna with frequency-selective or polarization-sensitive zones
DE112004001821T5 (en) Dielectric lens, dielectric lens device, dielectric lens design method, manufacturing method, and transmission lens of a dielectric lens
DE844177C (en) Arrangement for reducing the phase velocity of electromagnetic waves
DE60202778T2 (en) ELECTROMAGNETIC WINDOW
DE2211438B2 (en) Covering for antennas
DE2510854A1 (en) BANDPASS FILTER FOR MICROWAVES
DE69330034T2 (en) Waveguide lens and process for its manufacture
DE2753180A1 (en) CIRCULAR ANTENNA
DE830361C (en) Lens for radio directional antenna systems
DE112017001223B4 (en) Delay circuit
Franchi et al. Theoretical and experimental study of metal grid angular filters for sidelobe suppression
DE602005001762T2 (en) Microwave bandpass filter
DE3781089T2 (en) CORRUGATED REFLECTOR DEVICE AND FREE ELECTRON LASER METHOD.
DE69524546T2 (en) Frequency selective surface arrangement
DE3431986A1 (en) POLARIZATION SEPARATING REFLECTOR
EP0903806A2 (en) Quasi-optical filter and antenna arrangement with such a filter
DE69907948T2 (en) DIELECTRIC LAMINATED REFLECTOR FOR PARABOLA
DE2825432A1 (en) QUASI-OPTICAL BAND BARRIER FILTER
DE3801301C2 (en) Fresnel zone plate as a reflector for a microwave transmitting / receiving antenna
DE3644891A1 (en) RECEIVER FOR MICROWAVES AND MILLIMETER WAVES
DE836665C (en) Radio mirror arrangement
DE4336840C1 (en) Cover for radar antennas
DE69420368T2 (en) Biconical multimode resonator
DE2342904C3 (en) Directional antenna with low side lobes

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB IT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 19990318

AKX Designation fees paid

Free format text: DE FR GB IT SE

17Q First examination report despatched

Effective date: 20000204

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20020201