Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
  • H01Q9/04—Resonant antennas
  • H01Q9/0407—Substantially flat resonant element parallel to ground plane, e.g. patch antenna
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/27—Adaptation for use in or on movable bodies
  • H01Q1/28—Adaptation for use in or on aircraft, missiles, satellites, or balloons
  • H01Q1/286—Adaptation for use in or on aircraft, missiles, satellites, or balloons substantially flush mounted with the skin of the craft
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01Q—ANTENNAS, i.e. RADIO AERIALS
  • H01Q1/00—Details of, or arrangements associated with, antennas
  • H01Q1/27—Adaptation for use in or on movable bodies
  • H01Q1/28—Adaptation for use in or on aircraft, missiles, satellites, or balloons
  • H01Q1/288—Satellite antennas
• • 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
  • H01Q21/00—Antenna arrays or systems
  • H01Q21/06—Arrays of individually energised antenna units similarly polarised and spaced apart
  • H01Q21/061—Two dimensional planar arrays
• • 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
  • H01Q3/02—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 movement of antenna or antenna system as a whole
  • H01Q3/04—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 movement of antenna or antenna system as a whole for varying one co-ordinate of the orientation
• • 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
  • H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
  • H01Q3/30—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array
  • H01Q3/32—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array by mechanical means

Definitions

• the present invention relates to the field of flat satellite telecommunication antennas.
• the invention is particularly suitable for aircraft.
• the invention finds a particularly advantageous application for transmitting and receiving data to or from a satellite, particularly for satellite communications of the Satcom type (acronym for satellite communication or "satellite communications" in English terminology).
• These telecommunication antennas comprise a plane surface comprising at least one radiating line capable of transmitting and receiving signals of a frequency determined according to the shape of the radiating line.
• the signals are transmitted and received in the direction of the satellite which can be detuned with respect to the normal direction of the antenna according to the movements of the carrier. More specifically, these antennas must point a highly directional beam within a cone of at least 60 ° half-angle so that the gain of the antenna remains sufficient to ensure the signal-to-noise ratio necessary for the quality of the link.
• a known solution to achieve this pointing is to use a flat antenna 100 as described in Figure 1.
• This flat antenna 100 extends in an xy plane on an outer wall 101 of an aircraft.
• Radial lines 102 of the flat antenna 100 emit and receive signals in a detented direction 103 at an angle ⁇ to the z direction normal to the surface of the flat antenna 100 in the plane perpendicular to the radiating lines 102 ( xoz).
• This depointage requires adjustment of the phase on each radiating line by means for example of programmable electronic phase shifters.
• the phase ⁇ , to be displayed on the line i to obtain a score in the direction a is given by the expression:
• the flat antenna 100 is moreover rotatable ⁇ about an orthonormal axis z with the xy axes.
• This first solution makes it possible to scan electronically all the pointing directions inside the cone.
• the direction of the pointing at a is variable with the wavelength ⁇ and does not allow simultaneous operation in two very different frequency bands such as Satcom band Ka for example (20GHz in reception, 30GHz in transmission).
• ROTMAN lens described, for example, in US Pat. No. 3,170,158.
• the ROTMAN lens is a known device which usually makes it possible to obtain an antenna radiating several beams in a plane.
• the lens is provided with N access each giving a beam in a given direction independent of the frequency.
• the angular sweep is obtained by switching between the N beams available.
• the lens is formed by the space between two parallel conductive planes
• the input network consists of fixed horns made as a waveguide radiating a polarization perpendicular to the metal planes.
• the output network may consist of monopole elements perpendicular to the metal planes and to collect the energy radiated by the cornets of the input network.
• the linear array of the radiating elements is fed via links (coaxial for example) of lengths such that the radiated wave is plane.
• US Pat. No. 8,284,102 discloses an electronic phase shifter comprising an electronic selector for a linear or curved source array.
• the focusing of the antenna is performed by internal reflector elements and dielectric or refractive focusing means.
• This second solution makes it possible to have a fixed flat antenna on the surface of an aircraft.
• this solution limits the number of directions that can point the antenna according to the number of sources.
• the implementation of a linear source network and electronic selection means increases the size of the flat antenna.
• the present invention intends to overcome the drawbacks of the prior art by providing a fixed flat antenna provided with a mobile horn to scan continuously all directions.
• the present invention relates to a satellite telecommunication flat antenna comprising a radiant plate comprising at least one radiating line, and an adaptation means able to modify the delay of the fields transmitted or received by the at least one line.
• said adaptation means comprising a mobile horn rotating between two metal plates containing a sensor array, and at least one coaxial cable connected between at least one sensor of the network and the at least one radiating line, the length of the at least one coaxial cable being adapted to introduce a delay necessary for the focusing of the radiated wave by the radiating plate.
• the invention thus makes it possible to scan continuously all the directions associated with each position of the mobile horn.
• the invention makes it possible to fix the antenna on a flat surface thus limiting the fragility of the antenna and improving the aerodynamics of the wearer of the antenna.
• This antenna structure operates in a very wide frequency band because it gives an independent pointing of the frequency.
• the horn is able to transmit between the metal plates a wave whose electric field is perpendicular to the metal plates.
• said adaptation means also comprises a network of sensor monopoles attached to at least one metal plate, the at least one coaxial cable being connected between said network of sensor monopoles and the at least one radiating line.
• the sensor monopoles are connected in a network and able to take the energy emitted by the horn at a step less than 1 ⁇ 2 wavelength.
• the network of sensor monopoles may consist of simple metal strands (monopoles) or slots or any other type of elementary antenna. This embodiment thus makes it possible to transmit the energy picked up by the horn to the radiating lines.
• said network of sensor monopoles comprises a surface closed by a metal reflector.
• the metal reflector makes it possible to limit the radiation of the monopole network on the side of the horn.
• said metal reflector is positioned at 1 ⁇ 4 wavelength behind the sensor monopoles.
• the length of the at least one coaxial cable is adapted to introduce an additional delay making it possible to obtain an initial fixed score so that the total score varies from 0 ° to 60 ° for a symmetrical movement of the cornet of ⁇ 30 °.
• This embodiment associated with the overall rotation of the antenna 360 ° about its axis z can contain all directions in a 60 ° half-angle cone centered on the direction normal to the antenna.
• the two metal plates are fixed on a plane parallel to the plane of said radiating plate.
• said radiant plate comprises a plurality of radiating lines spaced by a half-wavelength approximately. This embodiment makes it possible in particular to avoid problems related to the network lobes. According to one embodiment, said radiant plate comprises a plurality of radiating lines consisting of an alignment of radiating elements such as dipoles, patches or slots.
• said radiating plate comprises a plurality of radiating lines each comprising a splitter with an input and a plurality of outputs corresponding to the number of radiating elements of the radiating line.
• Figure 1 illustrates a flat and mobile satellite telecommunications antenna according to the state of the art
• FIG. 2 illustrates a flat satellite telecommunications antenna according to one embodiment of the invention.
• Figure 3 illustrates the mobile horn of the antenna of Figure 2.
• FIG. 2 reveals a satellite dish antenna 10 consisting of a radiating plate 16 connected to an adaptation means 11 able to modify the delays of the fields transmitted or received by the radiating plate 16.
• the radiating plate 16 extends in a plane xy and has a plurality of radiating lines 17 disposed along the y-axis at a step close to half a wavelength along the x-axis.
• Each radiating line 17 consists of an alignment of N radiating elements (not shown), for example dipoles, patches or slots arranged at a pitch less than a wavelength along the y-axis and fed by a splitter with one input and N outputs.
• the adaptation means 1 1 consists of a horn 12 movable in rotation between two metal plates 13a and 13b parallel to the radiating plate 16.
• the horn 12 shown in Figure 3 is rotatable about the axis z '(parallel or confounded with the axis z) extending in a direction normal to the plane xy.
• the mobility of the horn 12 is provided by a digitally controlled guide 20.
• the horn 12 radiates between the two metal plates 13a, 13b a TEM wave (for electrical-magnetic transverse) whose electric field is perpendicular to the metal plates 13a, 13b.
• a network of monopoles 14 is fixed on the upper metal plate 13a in order to capture the TEM wave.
• the rear of the monopole network 14 is closed by a metal reflector 15 located at approximately 1 ⁇ 4 wavelength in order to close the adaptation means.
• Each monopole of the network 14 is connected to each radiating line 17 of the radiating plate 16 by means of a coaxial cable 18.
• the coaxial cables 18 are all of different lengths and introduce the delay necessary for the focusing of the radiated wave by the radiant plate 16. They also introduce an additional delay making it possible to obtain an initial fixed pointing so that the total score varies from 0 ° to 60 ° for a symmetrical displacement of the horn 12.
• the invention thus makes it possible to point all the directions contained in the 60 ° half-angle cone centered on the axis z by means of a rotation of the horn 12 of ⁇ 30 ° approximately around the axis z 'and a rotation of the antenna assembly 360 ° about the z axis.
• This antenna structure operates in a very wide band of frequencies because the mobile horn 12 provides a score independent of the frequency.

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• Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Astronomy & Astrophysics (AREA)
• General Physics & Mathematics (AREA)
• Remote Sensing (AREA)
• Aviation & Aerospace Engineering (AREA)
• Electromagnetism (AREA)
• Aerials With Secondary Devices (AREA)
• Variable-Direction Aerials And Aerial Arrays (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=52450219

Family Applications (1)

Country Status (5)

Families Citing this family (1)

Family Cites Families (4)

• 2014
  • 2014-06-13 FR FR1455391A patent/FR3022404B1/fr active Active
• 2015
  • 2015-06-08 WO PCT/EP2015/062681 patent/WO2015189134A1/fr active Application Filing
  • 2015-06-08 EP EP15728822.6A patent/EP3155689B1/de active Active
  • 2015-06-08 US US15/314,083 patent/US10038243B2/en active Active
  • 2015-06-08 ES ES15728822.6T patent/ES2676907T3/es active Active

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