EP0656671B1 - Orientierbare Antenne mit Bewahrung der Polarisationsachsen - Google Patents

Orientierbare Antenne mit Bewahrung der Polarisationsachsen Download PDF

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Publication number
EP0656671B1
EP0656671B1 EP94402741A EP94402741A EP0656671B1 EP 0656671 B1 EP0656671 B1 EP 0656671B1 EP 94402741 A EP94402741 A EP 94402741A EP 94402741 A EP94402741 A EP 94402741A EP 0656671 B1 EP0656671 B1 EP 0656671B1
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EP
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Prior art keywords
reflector
antenna
source
rotation
antenna according
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EP94402741A
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English (en)
French (fr)
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EP0656671A1 (de
Inventor
Véronique Courtonne
Dominique Morin
Jean-Claude Lacombe
Jean-Pierre Carbonell
Didier Rene
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Alcatel Espace Industries SA
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Alcatel Espace Industries SA
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
    • H01Q3/12—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems
    • H01Q3/16—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system using mechanical relative movement between primary active elements and secondary devices of antennas or antenna systems for varying relative position of primary active element and a reflecting device
    • 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
    • H01Q19/10—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 reflecting surfaces
    • H01Q19/18—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 reflecting surfaces having two or more spaced reflecting surfaces
    • H01Q19/19—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 reflecting surfaces having two or more spaced reflecting surfaces comprising one main concave reflecting surface associated with an auxiliary reflecting surface
    • H01Q19/191—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 reflecting surfaces having two or more spaced reflecting surfaces comprising one main concave reflecting surface associated with an auxiliary reflecting surface wherein the primary active element uses one or more deflecting surfaces, e.g. beam waveguide feeds
    • 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
    • H01Q19/10—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 reflecting surfaces
    • H01Q19/18—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 reflecting surfaces having two or more spaced reflecting surfaces
    • H01Q19/19—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 reflecting surfaces having two or more spaced reflecting surfaces comprising one main concave reflecting surface associated with an auxiliary reflecting surface
    • H01Q19/192—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 reflecting surfaces having two or more spaced reflecting surfaces comprising one main concave reflecting surface associated with an auxiliary reflecting surface with dual offset reflectors

Definitions

  • the field of the invention is that of antennas for the emission and / or reception of electromagnetic radiation, and more particularly directive and orientable antennas, capable of emitting and / or receiving radiation in a determined and variable direction.
  • Such an antenna may consist of a radiation source and one or more reflector (s), the shape of the reflector (s) and the arrangement of the DU system / reflectors relative to the source determining the directivity of the antenna thus formed as well as the shape of the beam emitted or received.
  • An offset system is a system comprising a main reflector, the cut of which is eccentric relative to the axis of the surface considered. In the case of a single reflector, the primary source located on this axis is inclined to target the center of the reflector.
  • the invention relates more particularly to antennas capable of transmitting and / or receiving according to two orthogonal linear polarizations, and the success of their mission of which depends on this capacity. This is the case for some telecommunications antennas, for example, which use polarization diversity to allow reuse of the spectrum in a given frequency band. Another example concerns antennas for satellite broadcasting in DBS (Direct Broadcast by Satellite) or DTH (Direct to the Home) systems. Independent measurements according to orthogonal polarizations are also carried out by certain equipment radar, to determine the radar signature of a complex target, for example, or for weather or earth observation radars.
  • DBS Direct Broadcast by Satellite
  • DTH Direct to the Home
  • the present invention for its part, will be particularly advantageous when deployed in space, on board a satellite, an orbital station, a probe, or any other space platform.
  • a geostationary telecommunications satellite in most cases, must be able to communicate with a relatively limited number of fixed ground stations.
  • the orientations of the axes of orthogonal polarizations used in such a system can be arbitrary provided that some initial adjustments are made to the equipment on the ground before the transmission of the useful information.
  • the constraint to accept is that in this case, no temporal variation of the geometric parameters of the link can be tolerated, without causing the need for a new sequence of settings. In the known art, this poses almost no drawback, since the geometric parameters of connection with a geostationary satellite are in principle invariable.
  • a linear polarization can be chosen parallel to the trajectory of the satellite, known a priori from ephemerides, and with the other polarization chosen perpendicular to this trajectory and to the nadir.
  • Each fixed station on the ground can know in advance the orientations of the polarization axes used by the satellite, and the antenna on the ground can be adjusted accordingly.
  • the reuse of frequencies by diversity of polarizations can also provide advantages for direct broadcasting by satellite.
  • a ground user will not be obliged to reorient his antenna to target a second satellite in order to receive a second "bouquet" of emissions, if a first satellite can provide the programs of this second bouquet, with those of the first bouquet, from the only orbital position of the first satellite, in cross polarizations.
  • the invention seeks to remedy the drawbacks of the prior art for telecommunications satellites (transmit and / or receive antenna) and direct broadcast satellites (transmit antenna only).
  • the polarization of the wave received by the equipment can be used to better probe the target.
  • backscattering and depolarization of a polarized wave emitted by the satellite can reveal the nature of atmospheric precipitation, since depolarization depends on the size, concentration, and phase state (ice, liquid in droplets). , vapor) of the probed compounds.
  • radar backscatter from the sea surface can reveal the state of sea agitation through polarization measurements.
  • the sensitivity to polarization is variable depending on the mission.
  • the polarization of the initial wave can be arbitrary without influencing the result obtained, precisely because the targets themselves are not fixed but on the contrary of arbitrary orientation.
  • the situation is different in the case where one would like to observe a fixed target, illuminated by a polarized wave at separate times in time.
  • Such successive measurements can be used to observe the evolution of the target over time, or to improve the signal-to-noise ratio and the resolution of the fixed image by correlation of the successive images (subtraction of the background).
  • a typical case is the observation of the same geographical area or the same object on the ground, during the successive passages of a traveling satellite.
  • the successive orbits of such a satellite are not generally closed when viewed from the earth's surface, but rather describe a spiral whose step advances in longitude. These are for example heliosynchronous orbits.
  • European patent application No. 0.139.482 describes an antenna intended to be used on board a satellite, this antenna being of the Cassegrain type and comprising a source, a primary reflector and a secondary reflector. The two reflectors are integral with one another and the source is fixed. Thus, the source is constantly maintained at the focal point of the antenna, regardless of the position of the reflectors.
  • This document does not however deal with the conservation of the orthogonal axes of polarization as a function of the pointing performed. In fact, it does not pose the problem linked to the targeting of non-circular spots, as will be seen later.
  • the new problem addressed by the invention is the following: we would like an antenna whose elements can be oriented at will to allow the arbitrary orientation of the beam of radiation emitted or received, while allowing conservation axes of orthogonal linear polarizations, whatever the orientation of the beam.
  • the antenna according to the invention must allow the conservation of the axes of orthogonal linear polarizations even in the case of a rotation of the beam around its main direction of propagation.
  • the invention proposes an antenna according to claims 1 or 14.
  • the source can be a simple horn, a microstrip radiator ("patch" in English), a slot, ... or the source can be a complex or extended source, for example a network of patches or slots, possibly in association with cavities.
  • the complex source can be a plurality of separate sources, with a selective polarization reflector or with a plurality of frequency selective reflectors.
  • the source can be a direct source or a periscopic source. In short, the invention can be carried out using any source known to those skilled in the art for such applications.
  • the movement of at least one reflector comprises a rotation of the reflector around the preferred direction of radiation.
  • this movement comprises an angular displacement (deflection) of the preferred direction around a point which represents the position of the source.
  • the movement comprises a rotation of the reflector around the direction of propagation of radiation which connects the source and the reflector.
  • the direction of propagation between the source and the reflector coincides with the preferred direction of radiation.
  • the reflector is a single reflector having parabolic generators, this reflector being illuminated by a source arranged substantially in its focus, and the reflector can be rotated around the direction of radiation while the source is kept fixed.
  • the geometry of the assembly is in this case centered.
  • the single parabolic reflector is illuminated by a source arranged in an "offset" geometry and the reflector can be rotated around the direction of radiation while the source is held stationary.
  • the antenna comprises at least two reflectors arranged in a geometry called "Gregory", offset or centered.
  • the two reflectors are arranged with their concave surfaces facing each other, each of them being illuminated either in offset or in center.
  • the antenna comprises at least two reflectors arranged in a Cassegrain geometry, including a main reflector which reflects the beam, and an auxiliary reflector which is illuminated by the source. At least the main reflector can be rotated around the preferred direction of radiation while the source is kept stationary. Alternatively, all of the reflectors can be rotated around the preferred direction of radiation while the source is held stationary.
  • the antenna further comprises mechanical means for deflecting all of the constituents, without modification of their relative arrangement, in addition to the mechanical means previously described.
  • the reflector can be simple or complex.
  • a complex reflector can for example be a bigrille reflector consisting of two reflectors arranged one in front of the other in a direction of propagation of the beam, the first reflector having to be reflective for a first linear polarization, and transparent for a second orthogonal linear polarization , which will be reflected by the second reflector located behind said first reflector.
  • a bigrille reflector is well known to those skilled in the art.
  • the mechanical means allow the rotation of the source, of any shape, while keeping the reflector (s) fixed.
  • Figure 1 schematically shows a satellite Q in Earth orbit.
  • the satellite has a steerable antenna; according to the position of the reflector 11, the beam can be directed in different directions, to illuminate different places on the earth E.
  • the beam F directed according to the nadir illuminate the "spot" 1
  • the beams respectively F ', F' 'illuminate the spots 1', 1 '' spot is the English word used by those skilled in the art to designate the path on the ground of a narrow beam directed towards the earth E).
  • the beam can be oriented either mechanically by positioning a main reflector 11 as shown schematically in this figure, or electronically in the case of a network antenna by playing on the phases applied to the elementary sources of the network.
  • the description of the antenna of the invention will be made in transmission but it is understood that the invention also relates to a reception antenna having the same characteristics, as well as a transmission / reception antenna such as a radar or telecommunications antenna.
  • the amplification electronics associated with the antenna must be adapted: either to the power amplification for an antenna at transmission, or to the low noise amplification at reception, or both for a transmit / receive antenna.
  • the spot 1 has the shape of an ellipse having axes a, b; the ellipse being elongated along the axis a.
  • the axes x, y of polarization coincide with the axes a, b of the elliptical spot 1.
  • a rotation of the antenna around the main axis of the beam is obtained by mechanical means which physically rotate the antenna around this main axis.
  • this antenna is supplied by one or more sources along two axes of linear orthogonal polarization
  • the axes of polarization undergo the same rotation as the axes of the spot on the ground.
  • the rotation of the axes of polarization cannot be tolerated, since it would inevitably cause interference between the signals conveyed by channels which are distinct and separated only by their polarization.
  • the antenna of the invention makes it possible to solve this problem and to obtain the result illustrated in FIG. 2.
  • the spots 1 ', 1'' can be illuminated by a translation and a rotation of the elliptical spot 1, but that the axes of polarization (x, y) are preserved whatever the orientation of the axes (a ', b'; a '', b '') of the elliptical spot (1 ', 1''respectively).
  • the elliptical spots are oriented to better cover the geographic areas indicated on a geopolitical map of Europe.
  • FIG. 3 shows schematically and in side section a parabolic antenna of the prior art.
  • the essential elements of this antenna are the focusing reflector 11 having the shape of a paraboloid of revolution around the axis of symmetry z, and the source 10 placed at the focus of the reflector 11.
  • the source of this example is a horn 10 supplied by a waveguide 12.
  • Mechanical means 13 are provided to maintain the source 10 at the focus of the reflector 11, in a fixed and optimal geometric arrangement.
  • the electromagnetic radiation emitted by the source 10 at the focus is reflected by the reflector 11 according to parallel rays which form a beam F of radiation along the main axis z.
  • FIGS. 4A, 4B, 4C are shown different views of an asymmetrical parabolic reflector, capable of making an elongated spot on the ground.
  • the shape of the reflector 11 when viewed in plan in FIG. 4B is almost rectangular.
  • the sections AA ', BB' shown respectively in FIGS. 4A, 4C, are arcs of paraboloids of different lengths. The arcs can have the same focal length, despite their different lengths, and the reflector 11 will have a single focus. The beam resulting from a source at the focus will have a rectangular section.
  • FIG. 5 shows in axial section a conventional Cassegrain geometry, which comprises a source 10 which illuminates an auxiliary reflector 21 through a hole 20 in a main parabolic reflector 11.
  • the conventional geometry is axisymmetric around the z axis which corresponds to the direction of propagation of the beam F.
  • the source 10 is either arranged on the z axis, or (in a variant not shown) imaged on the axis using a third periscope reflector (not shown).
  • the auxiliary reflector 21 in the form of a hyperboloid, the first focus C of which coincides with the focal point of the main parabolic reflector 11, while the phase center of the source 10 is imaged at the second focus C 'of the hyperboloid.
  • a ray emitted by the source 10 of the point C 'at an angle of ⁇ with respect to the axis z will be reflected from the surface of the auxiliary reflector 21 towards the main reflector 11 in a direction which will have for its origin the focal point C of the main parabolic reflector 11.
  • the rays arriving from the focal point C are reflected by the main parabolic reflector by a reflection angle ⁇ 'to form a beam F whose all the rays are parallel to the axis z.
  • the vector N represents the normal to the surface of the auxiliary reflector 21. and the vector N 'represents the normal to the surface of the main reflector 11.
  • Figure 6 shows schematically and in three dimensions in perspective the parabolic reflector (11) of Figures 4A, 4B, 4C, with a coordinate system which makes it possible to describe the movements of the antenna according to the invention.
  • the top of the reflector 11 is located at the origin 0, and the axis z represents the direction of propagation of the reflected waves (not shown).
  • the parabolic reflector 11 has an approximate rectangular shape when viewed in projection on a flat surface perpendicular to the z axis, for example the plane (x, y).
  • D is its width in the direction x, and D 'is its height in the direction y.
  • a section AA 'in the plane (x, z) describes a parabola
  • a section B'B in the plane (y, z) describes a parabola, in accordance with FIGS. 4A 4B and 4C.
  • the system has three degrees of freedom of movement: rotation by an angle ⁇ around the axis principal z; and a depointing which can be described by two angles ( ⁇ , ⁇ ) in two orthogonal planes whose intersection is the main axis z.
  • the depointing can be represented by the unit vector u ⁇ which is oriented along the angles of directions ( ⁇ , ⁇ , ⁇ ,) to arrive at a point P outside the z axis.
  • the angle ⁇ can be expressed as a function of the two independent variables ( ⁇ , ⁇ ).
  • the angle ⁇ represents the projection of the vector u ⁇ on the plane (x, y), and the point M the projection of the point P on this same plane (x, y).
  • the angle ⁇ represents the projection of the vector u ⁇ on the plane (y, z).
  • the projection of point P on this plane is not shown for reasons of clarity of the drawing.
  • a rotation of the reflector can be represented either by the angle ⁇ around the main axis z, or by the angle ⁇ 'around the unit vector u ⁇ ; these angles are not independent of each other.
  • the assembly comprising the source (10), the reflectors (11, 21) and the mechanical positioning means (depointing, rotation) is fixed by means of the supports S 3 to the platform Q, a satellite for example.
  • the positioning means comprise three stepping motors (R ⁇ , R ⁇ , R ⁇ ) capable of effecting angular displacements ( ⁇ , ⁇ , ⁇ ) explained in FIG. 6. These means are mounted on a small platform Q 'which rests on supports S 3 .
  • the deflection means (R ⁇ , R ⁇ ) are fixed on the small platform Q 'and drive the support S 2 which supports the axial rotation motor R ⁇ .
  • This axial rotation motor R ⁇ is mechanically fixed to the main reflector 11 to perform a rotation ( ⁇ ) of the latter around the main axis z. Unlike the antennas known in the prior art, the rotation of the main reflector 11 does not cause the rotation of the source 10, which is not fixed to the reflector 11.
  • the source 10 is supplied with two orthogonal polarizations which also remain fixed relative to the source 10 during a rotation ⁇ of the main reflector.
  • FIG. 9 the same embodiment in FIG. 8 is shown in three dimensions and in perspective seen from above.
  • the elements already described in Figure 8 have the same references.
  • This characteristic already present in the centered Cassegrain geometry, is used according to the invention to isolate the source 10 of rotations ⁇ of the main reflector and of the auxiliary reflector linked to the main 11 around the z axis.
  • the projections of points A, A '; B, B 'on the x plane, y are the points a, a'; b, b 'respectively, and gives the lateral dimensions of the main reflector 11 and of the auxiliary reflector 21 fixed to the main reflector 11 by the support rods S 1 .
  • these lateral dimensions (aa ', bb') are unequal, and the section of the beam F (not shown) can have an arbitrary shape determined by the shape of the perimeter of the main reflector 11, elliptical in this example.
  • the source 10 of this example is a horn, but can be produced according to any other technology known to those skilled in the art.
  • the source 10 can be a network of elementary sources produced in microstrip technology.
  • FIG. 10 schematically shows in axial section another embodiment according to the invention which represents a variant of the antenna shown in FIGS. 8 and 9.
  • auxiliary periscopic reflector 14 which receives the radiation from the source 10 offset on the z 'axis parallel to the x axis and perpendicular to the main z axis .
  • This auxiliary reflector 14 is arranged in such a way that it reflects the radiation from the source 10 along the z axis to illuminate the hyperbolic auxiliary reflector 21. Everything then takes place according to the description which has been made of FIGS. 8 and 9.
  • the source 10 remains stationary relative to the platforms Q and Q ', even during a rotation ⁇ of the main and auxiliary reflector 11 by the motor R ⁇ .
  • the position of the auxiliary reflector 14 is adjusted to hold the reflection of the radiation from the source 10 along the main axis z to illuminate the auxiliary reflector 21.
  • FIG. 11 shows schematically and in partial section another example of an embodiment according to the invention of an adjustable offset Cassegrain antenna with polarization conservation.
  • the main parabolic reflector 11 is illuminated by the source 10 via an auxiliary reflector 15.
  • the main reflector is offset offset by the auxiliary reflector at an angle of ⁇ relative to the normal N 'of the main reflector 11 at its summit; the beam F (not shown) is reflected at the same angle ⁇ of the normal N 'along the main axis z.
  • the beam deflection is obtained in this example by positioning the main reflector by the means R ⁇ , R ⁇ .
  • Different mechanical means of static support are shown (S 5 , S 6 , S 7 ), as well as a removable support S 4 which supports the platform Q '' along the main axis z, while allowing its movement in a perpendicular plane to z.
  • Different means of thermal insulation I 1 , I 2 ) are also shown in this figure.
  • the main axis z is distant from the illumination axis z 'of the auxiliary reflector 15, and the two axes are parallel.
  • a mobile platform Q '' on which the main reflector 11 and the means of the support (S 5 , S 6 , S 7 ) and of depointing (R ⁇ , R ⁇ ) of the latter are mounted, can be moved by the means R ⁇ d ' an angle ⁇ around the z axis of primary illumination. Since the source 10 remains fixed relative to the platform Q (a satellite for example) during a rotation ⁇ around the axis z ', the axes of polarization remain invariant with respect to the platform Q.
  • the support means S 8 of the auxiliary reflector 15 connects the latter to the mobile platform Q '', which means that a rotation of the latter does not cause any modification the relative geometry of the two main 11 and auxiliary 15 reflectors.
  • the depointing means are mechanical and act on the main reflector, but the invention can also make use of electronic depointing (by phase shifts of the elementary sources in the network) or else, to a depointing effected by mechanical means which act on an auxiliary or auxiliary periscope reflector.
  • the rotation of the spot formed on the ground can be obtained either by a rotation ⁇ around the main axis (z), or by a rotation ⁇ of the reflector system (s) around the axis of primary illumination z ', or by a rotation ⁇ ' around a depointed main axis u ⁇ .
  • a decoupling of the deflection means and of rotation means around one of the axes (z, z ', u ⁇ ) propagation of electromagnetic radiation allows the orientation of the beam with conservation of the polarization.

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Claims (14)

  1. Satellitenantenne mit mindestens einem Reflektor (11) und mindestens einer Quelle (10) einer elektromagnetischen Strahlung, wobei mindestens eine der Quellen (10) mindestens ein strahlendes Element sowie Mittel zur Anregung dieses Elements gemäß zwei linearen und zueinander senkrecht stehenden charakteristischen Polarisationen aufweist und wobei mindestens ein Reflektor fokussierend wirkt, wobei die Antenne weiter mechanische Mittel (S1, S2, ...) besitzt, die die Quellen (10) mit den Reflektoren (11) verbinden und ihre Positionierung gewährleisten, wobei die Antenne eine elektromagnetische Strahlung F gemäß einer bevorzugten Strahlungsrichtung (z) senden oder empfangen kann und diese Strahlung F einen Spot auf der Erdoberfläche bestrahlen soll, wobei die mechanischen Positioniermittel (S1, S2, Rϕ, ...) eine Bewegung mindestens eines Reflektors (11) bezüglich der bevorzugten Strahlungsrichtung ermöglichen, dadurch gekennzeichnet, daß der Spot nicht kreisförmig ist und daß die mechanischen Mittel (S1, S2, Rϕ) so ausgebildet sind, daß der Reflektor (11) eine Drehung (ϕ, φ, ϕ') um eine Ausbreitungsachse (z, z', u →
    Figure imgb0009
    ) der elektromagnetischen Strahlung durchführen kann, so daß sich eine Drehung des Spots um die durch die bevorzugte Abstrahlungsrichtung definierte Achse ergibt, während die Quelle (10) in einer solchen Stellung bleibt, daß die Polarisationsachsen in dem Spot bei dieser Drehung (ϕ, φ, ϕ') unverändert bleiben.
  2. Antenne nach Anspruch 1, dadurch gekennzeichnet, daß die Drehung eine Drehung ϕ um die Hauptachse (z) ist, die die bevorzugte Strahlungsrichtung darstellt, wobei die Drehung durch mechanische Drehmittel Rϕ bewirkt wird, die die Anordnung mindestens eines der Reflektoren (11) verändern und dabei die Lage der Quelle (10) unverändert lassen.
  3. Antenne nach Anspruch 1, dadurch gekennzeichnet, daß die Drehung eine Drehung φ um eine Hilfsachse (z') ist, die die Quelle (10) mit einem sogenannten Hilfsreflektor (15) verbindet, wobei die Drehung durch mechanische Drehmittel Rφ bewirkt wird, die auf die Anordnung mindestens eines Reflektors (11) einwirken und dabei die Lage der Quelle (10) unverändert lassen.
  4. Antenne nach einem beliebigen der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß die Hilfsachse (z') die gleiche wie die Achse ist, die die bevorzugte Abstrahlungsrichtung z definiert, und daß die Antenne eine koaxiale Geometrie besitzt.
  5. Antenne nach einem beliebigen der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß sie eine Cassegrain-Geometrie vom zentrierten oder Offset-Typ besitzt.
  6. Antenne nach einem der Ansprüche 1, 2 oder 4, mit einem parabolischen Hauptreflektor (11), der von einer in dessen Brennpunkt liegenden Quelle (10) bestrahlt wird, dadurch gekennzeichnet, daß der parabolische Hauptreflektor (11) um die privilegierte Abstrahlungsrichtung z gedreht werden kann, während die Quelle (10) nicht mitdreht.
  7. Antenne nach einem beliebigen der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß es sich um eine Gregory-Geometrie vom zentrierten oder Offset-Typ handelt.
  8. Antenne nach einem beliebigen der Ansprüche 1 bis 7, dadurch gekennzeichnet, daß sie weiter Schwenkmittel (Rα, Rβ) aufweist, die die bevorzugte Abstrahlungsrichtung z verändern können, ohne zugleich die Polarisationsachsen im Spot zu verändern.
  9. Antenne nach einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, daß sie eine Sende- und/oder Empfangsantenne ist.
  10. Antenne nach einem der Ansprüche 1 bis 9, dadurch gekennzeichnet, daß sie weiter eine komplexe primäre Quelle (10) aufweist.
  11. Antenne nach Anspruch 10, dadurch gekennzeichnet, daß die komplexe Primärquelle (10) mehrere getrennte Quellen enthält und daß die Antenne außerdem mindestens einen polarisationsselektiven Reflektor besitzt.
  12. Antenne nach Anspruch 11, dadurch gekennzeichnet, daß die komplexe Primärquelle (10) mehrere getrennte Quellen aufweist und daß die Antenne weiter mehrere frequenzselektive Reflektoren enthält.
  13. Antenne nach Anspruch 10, dadurch gekennzeichnet, daß die komplexe Primärquelle (10) mindestens eine periskopische Quelle besitzt.
  14. Antenne für einen Satelliten mit mindestens einem Reflektor (11) und mindestens einer elektromagnetischen Strahlungsquelle (10), wobei mindestens eine der Quellen (10) mindestens ein strahlendes Element sowie Mittel zur Anregung dieses Elements besitzt, wobei mindestens ein Reflektor zwei Gitter und die Antenne weiter mechanische Mittel (S1, S2, ...) besitzt, die die Quellen und die Reflektoren (11) koppeln und ihre Positionierung gewährleisten, wobei die Antenne eine elektromagnetische Strahlung F gemäß einer bevorzugten Strahlungsrichtung z aussenden oder empfangen kann, wobei die Strahlung F zueinander senkrecht stehende Polarisationsachsen besitzt, die durch die Orientierung der Gitter des Reflektors (11) erzeugt werden, wobei die Strahlung F einen Spot auf der Erdoberfläche bestrahlen soll und die mechanischen Positioniermittel (S1, S2, Rϕ, ...) die Bewegung mindestens eines Reflektors bezüglich der bevorzugten Strahlungsrichtung erlauben, dadurch gekennzeichnet, daß der Spot nicht kreisförmig ist und daß die mechanischen Positioniermittel (S1, S2, Rϕ, ...) so ausgebildet sind, daß sie eine Drehung (ϕ, φ, ϕ') der Quelle (10) und eine Drehung des Spots um die durch die bevorzugte Strahlungsrichtung z definierte Achse bewirken, während zugleich der Reflektor (11) mit den beiden Gittern in einer solchen Position bleibt, daß die Polarisationsachsen in dem Spot bei dieser Drehung nicht verändert werden.
EP94402741A 1993-12-02 1994-11-30 Orientierbare Antenne mit Bewahrung der Polarisationsachsen Expired - Lifetime EP0656671B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9314452A FR2713404B1 (fr) 1993-12-02 1993-12-02 Antenne orientale avec conservation des axes de polarisation.
FR9314452 1993-12-02

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EP0656671A1 EP0656671A1 (de) 1995-06-07
EP0656671B1 true EP0656671B1 (de) 1996-08-14

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EP94402741A Expired - Lifetime EP0656671B1 (de) 1993-12-02 1994-11-30 Orientierbare Antenne mit Bewahrung der Polarisationsachsen

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EP (1) EP0656671B1 (de)
AU (1) AU7891094A (de)
DE (1) DE69400372T2 (de)
FR (1) FR2713404B1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109301498A (zh) * 2018-09-13 2019-02-01 芜湖博高光电科技股份有限公司 一种新型3mm波段天线塑料镀膜副反射面支架

Families Citing this family (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3313636B2 (ja) * 1997-12-22 2002-08-12 日本電気株式会社 低軌道衛星通信用アンテナ装置
EP1082778A2 (de) 1998-05-20 2001-03-14 L-3 Communications Essco, Inc. Mehrfachkeulenantenne für satellitenkommunikation
US6043788A (en) * 1998-07-31 2000-03-28 Seavey; John M. Low earth orbit earth station antenna
US6397039B1 (en) * 1998-09-14 2002-05-28 Space Systems/Loral, Inc. Satellite communication system using multiple ground station RF power control in a single downlink beam
US6496682B2 (en) 1998-09-14 2002-12-17 Space Systems/Loral, Inc. Satellite communication system employing unique spot beam antenna design
US6266024B1 (en) * 1998-12-23 2001-07-24 Hughes Electronics Corporation Rotatable and scannable reconfigurable shaped reflector with a movable feed system
US6331839B1 (en) 1999-03-17 2001-12-18 Burt Baskette Grenell Satellite antenna enhancer and method and system for using an existing satellite dish for aiming replacement dish
US6215453B1 (en) 1999-03-17 2001-04-10 Burt Baskette Grenell Satellite antenna enhancer and method and system for using an existing satellite dish for aiming replacement dish
GB9914162D0 (en) * 1999-06-18 1999-08-18 Secr Defence Brit Steerable transponders
GB2368467B (en) * 2000-10-25 2002-09-11 Stanford Components Ltd Satellite signal receiving unit
US6342865B1 (en) * 2000-11-29 2002-01-29 Trw Inc. Side-fed offset cassegrain antenna with main reflector gimbal
US6563473B2 (en) * 2001-02-22 2003-05-13 Ems Technologies Canada, Ltd. Low sidelobe contiguous-parabolic reflector array
ES2250322T3 (es) * 2001-07-20 2006-04-16 Eutelsat Sa Antena de alto rendimiento y bajo coste para empleo en terminales de transmision/recepcion por satelite.
US6628238B2 (en) * 2001-11-19 2003-09-30 Parthasarathy Ramanujam Sub-reflector for dual-reflector antenna system
US7030831B2 (en) * 2002-11-14 2006-04-18 Wifi-Plus, Inc. Multi-polarized feeds for dish antennas
JP4150778B2 (ja) * 2003-01-28 2008-09-17 オプテックス株式会社 ３軸調整型の物体検知装置
US6972480B2 (en) 2003-06-16 2005-12-06 Shellcase Ltd. Methods and apparatus for packaging integrated circuit devices
WO2005018049A1 (ja) * 2003-08-13 2005-02-24 Mitsubishi Denki Kabushiki Kaisha 反射鏡アンテナ装置
GB0421956D0 (en) 2004-10-02 2004-11-03 Qinetiq Ltd Antenna system
US7109937B2 (en) * 2004-11-29 2006-09-19 Elta Systems Ltd. Phased array planar antenna and a method thereof
US7755557B2 (en) * 2007-10-31 2010-07-13 Raven Antenna Systems Inc. Cross-polar compensating feed horn and method of manufacture
DE102008011350A1 (de) * 2008-02-27 2009-09-03 Loeffler Technology Gmbh Vorrichtung und Verfahren zur Echtzeiterfassung von elektromagnetischer THz-Strahlung
EP2161784A1 (de) * 2008-09-05 2010-03-10 Astrium Limited Antennenreflektor
US9190716B2 (en) * 2008-09-05 2015-11-17 Astrium Limited Reflector
US9774095B1 (en) * 2011-09-22 2017-09-26 Space Systems/Loral, Llc Antenna system with multiple independently steerable shaped beams
EP2911245B1 (de) * 2012-10-16 2020-10-28 Mitsubishi Electric Corporation Reflektorantennenvorrichtung
ES2900731T3 (es) * 2014-09-10 2022-03-18 Macdonald Dettwiler And Associates Corp Antena direccionable de exploración ancha
CN106410411A (zh) * 2016-11-14 2017-02-15 中国电信股份有限公司深圳分公司 一种用于天线控制系统的转台装置
US10938103B2 (en) 2018-05-22 2021-03-02 Eagle Technology, Llc Antenna with single motor positioning and related methods
WO2020095310A1 (en) * 2018-11-08 2020-05-14 Orbit Communication Systems Ltd. Low Profile Multi Band Antenna System
CN110334480B (zh) * 2019-07-26 2022-11-22 中国电子科技集团公司第五十四研究所 用于降低噪声温度的双偏置天线副面扩展曲面设计方法

Family Cites Families (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US842351A (en) * 1906-02-19 1907-01-29 Walter Stock Christmas-music apparatus.
US3276022A (en) * 1964-05-13 1966-09-27 Aeronca Mfg Corp Dual frequency gregorian-newtonian antenna system with newtonian feed located at common focus of parabolic main dish and ellipsoidal sub-dish
US3407404A (en) * 1964-10-05 1968-10-22 Bell Telephone Labor Inc Directive microwave antenna capable of rotating about two intersecting axes
US3562753A (en) * 1968-02-23 1971-02-09 Hitachi Ltd Casseyrain antenna system with rotatable main reflector for scanning
US3696432A (en) * 1971-01-15 1972-10-03 Motorola Inc Combined scan and track antennas
US3795003A (en) * 1973-02-26 1974-02-26 Us Army Schwarzschild radar antenna with a unidirectional turnstile scanner
DE2321613A1 (de) * 1973-04-28 1974-11-14 Rohde & Schwarz Umschaltvorrichtung fuer das erregersystem einer reflektorantenne
US3914768A (en) * 1974-01-31 1975-10-21 Bell Telephone Labor Inc Multiple-beam Cassegrainian antenna
FR2429505A1 (fr) * 1978-06-20 1980-01-18 Thomson Csf Systeme d'alimentation periscopique pour antenne bi-gamme
FR2498820A1 (fr) * 1981-01-23 1982-07-30 Thomson Csf Source hyperfrequence bi-bande et antenne comportant une telle source
US4535338A (en) * 1982-05-10 1985-08-13 At&T Bell Laboratories Multibeam antenna arrangement
US4755826A (en) * 1983-01-10 1988-07-05 The United States Of America As Represented By The Secretary Of The Navy Bicollimated offset Gregorian dual reflector antenna system
JPS6089104A (ja) * 1983-09-22 1985-05-20 ブリテイツシユ・エアロスペイス・パブリツク・リミテツド・カンパニー アンテナ装置
US4668955A (en) * 1983-11-14 1987-05-26 Ford Aerospace & Communications Corporation Plural reflector antenna with relatively moveable reflectors
US4786912A (en) * 1986-07-07 1988-11-22 Unisys Corporation Antenna stabilization and enhancement by rotation of antenna feed

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109301498A (zh) * 2018-09-13 2019-02-01 芜湖博高光电科技股份有限公司 一种新型3mm波段天线塑料镀膜副反射面支架

Also Published As

Publication number Publication date
AU7891094A (en) 1995-06-08
DE69400372T2 (de) 1996-12-12
US5796370A (en) 1998-08-18
FR2713404B1 (fr) 1996-01-05
FR2713404A1 (fr) 1995-06-09
DE69400372D1 (de) 1996-09-19
EP0656671A1 (de) 1995-06-07

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