Multifocal receiving antenna with a single aiming direction for several satellites

Claim 2

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a spacing equal to a whole number of wavelengths of the radiation of a predetermined wavelength to be received, said reflector having a quasi-flat structure with respect to a direction along said axes, said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a paraboloid in which the paraboloid of the first of said sectors forms a central zone, and a second of said sectors is a sector of a paraboloid in which the paraboloid of the second of said sectors forms an external zone, and wherein said central zone is within said external zone.

Claim 3

The antenna of claim 1, wherein the sources are surface wave sources formed from helicoidal illuminators respectively connected to low noise amplifiers by coaxial cables.

Claim 4

The antenna according to claim 2, wherein two helicoidal illuminators are provided which are respectively adapted for the reception of right and left circular polarization components of the radiation.

Claim 5

The antenna of claim 3, wherein the sectors of paraboloids have the same axis, which is also the axis of helicoids of the helicoidal illuminators, the foci of the sectors of the paraboloids being spaced on said same axis by K λ, and each sector having a symmetry of revolution about said same axis, wherein K is an integer and λ is the wavelength of radiation to be received.

Claim 6

The antenna of claim 4, wherein the sector of a paraboloid having the shortest focal length is provided in a central section in order to form said first sector, said second sector of a paraboloid having the shape of a ring and having an inner diameter equal to an outer diameter of the first sector having the shortest focal length.

Claim 7

The antenna of claim 2, wherein the at least two sectors of paraboloids have parallel axes spaced by K λ, the foci of said sectors and the helicoids of said helicoidal illuminators respectively located on said parallel axes, and wherein an axis extending from a focal point on one axis to a focal of another axis is orthogonal to both of the parallel axes.

Claim 8

The antenna of claim 4, wherein helicoids of the helicoidal illuminators having the same axis are both excited from a rear direction in a back-fire mode.

Claim 9

The antenna of claim 7, wherein points of connection of the helicoids to coaxial cables are located on their common axis.

Claim 10

The antenna of claim 4, wherein each of the two helicoids is connected to a respective coaxial cable, the two cables being symmetrically located with respect to the axis in the sections where they are separated and at a sufficient distance from the helicoids, such that an assembly formed by the helicoids is capable of receiving a protective radome.

Claim 11

The antenna of claim 9, wherein the coaxial cables connected to the two sources pass through a center of one sector of said sectors of paraboloids.

Claim 12

The antenna of claim 5, wherein the first and second sectors of paraboloids are mechanically connected by a section of a cone.

Claim 13

The antenna of claim 1, wherein at least one of the sectors of paraboloids is constituted from several sectors of different paraboloids whose virtual apices are offset by a whole number of half wavelengths, focusing the radiation at a same focus, said several sectors connected by sections of cones in order to reduce size.

Claim 14

The antenna of claim 1, wherein the reflector formed of sectors of paraboloids has a cross-sectional projection area of rectangular shape.

Claim 15

The antenna of claim 13, wherein the projection area is square in cross section.

Claim 16

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a whole number of wavelengths of the radiation of a predetermined wavelength to be received; said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a paraboloid which forms a central zone, and a second of said sectors is a sector of a paraboloid which forms an external zone, and wherein said central zone is within said external zone; wherein the sources are surface wave sources formed from helicoidal illuminators respectively connected to low noise amplifiers by coaxial cables; wherein two helicoidal illuminators are provided which are respectively adapted for the reception of right and left circular polarization components of the radiation; and wherein an electromagnetic absorber is disposed between the two helicoidal illuminators such that the helicoidal illuminator which is most distant from the reflecting surfaces of the sectors of paraboloids is not disturbed by a backward wave focused on the other helicoidal illuminator.

Claim 17

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a whole number of wavelengths of the radiation of a predetermined wavelength to be received; said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a paraboloid which forms a central zone, and a second of said sectors is a sector of a paraboloid which forms an external zone, and wherein said central zone is within said external zone; wherein the sources are surface wave sources formed from helicoidal illuminators respectively connected to low noise amplifiers by coaxial cables; wherein two helicoidal illuminators are provided which are respectively adapted for the reception of right and left circular polarization components of the radiation; and wherein an electromagnetic absorber is disposed between the two helicoidal illuminators such that the helicoidal illuminator which is most distant from the reflecting surfaces of the sectors of paraboloids is not disturbed by a backward wave focused on the other helicoidal illuminator.

Claim 18

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a whole number of wavelengths of the radiation of a predetermined wavelength to be received; said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a paraboloid which forms a central zone, and a second of said sectors is a sector of a paraboloid which forms an external zone, and wherein said central zone is within said external zone; wherein the sources are surface wave sources formed from helicoidal illuminators respectively connected to low noise amplifiers by coaxial cables; wherein two helicoidal illuminators are provided which are respectively adapted for the reception of right and left circular polarization components of the radiation; wherein the sectors of paraboloids have the same axis, which is also the axis of helicoids of the helicoidal illuminators, the foci of the sectors of the paraboloids being spaced on said same axis by K λ, and each sector having a symmetry of revolution about said same axis, wherein K is an integer and λ is the wavelength of radiation to be received; and wherein one of the helicoids having the same axis is excited from a rear direction in a back-fire mode, and another helicoid is excited from an endward direction in an end-fire mode.

Claim 19

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a whole number of wavelengths of the radiation of a predetermined wavelength to be received; said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a paraboloid which forms a central zone, and a second of said sectors is a sector of a paraboloid which forms an external zone, and wherein said central zone is within said external zone; wherein the sources are surface wave sources formed from helicoidal illuminators respectively connected to low noise amplifiers by coaxial cables; wherein two helicoidal illuminators are provided which are respectively adapted for the reception of right and left circular polarization components of the radiation; wherein the sectors of paraboloids have the same axis, which is also the axis of helicoids of the helicoidal illuminators, the foci of the sectors of the paraboloids being spaced on said same axis by K λ, and each sector having a symmetry of revolution about said same axis, wherein K is an integer and λ is the wavelength of radiation to be received; and wherein one of the helicoids having the same axis is excited from a rear direction in a back-fire mode, and another helicoid is excited from an endward direction in an end-fire mode.

Claim 20

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a spacing equal to a whole number of wavelengths of the radiation of a predetermined wavelength to be received, said reflector having a quasi-flat structure with respect to a direction along said axes; said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a first paraboloid, said first paraboloid forming a central zone, and the second of said sectors is a sector of a second paraboloid, said second paraboloid forming an external zone, and wherein said central zone is within said external zone, wherein said respective axes of the paraboloids of the first and second sectors extend along a common axis, with the foci of said first and second sectors spaced from each other on said common axis, and wherein a spacing between the respective foci of said first and second sectors along said common axis is equal to Kλ, wherein K is an integer greater than zero, and λ is the wavelength of radiation to be received.

Claim 21

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a spacing equal to a whole number of wavelengths of the radiation of a predetermined wavelength to be received, said reflector having a quasi-flat structure with respect to a direction along said axes; said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a first paraboloid, said first paraboloid forming a central zone, and the second of said sectors is a sector of a second paraboloid, said second paraboloid forming an external zone, and wherein said central zone is within said external zone, wherein said respective axes of the paraboloids of the first and second sectors extend along a common axis, with the foci of said first and second sectors spaced from each other on said common axis, and wherein a spacing between the respective foci of said first and second sectors along said common axis is equal to Kλ, wherein K is an integer greater than zero, and λ is the wavelength of radiation to be received.

Claim 22

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a spacing equal to a whole number of wavelengths of the radiation of a predetermined wavelength to be received, said reflector having a quasi-flat structure with respect to a direction along said axes, said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a first paraboloid, said first paraboloid forming a central zone, and the second of said sectors is a sector of a second paraboloid, said second paraboloid forming an external zone, and wherein said central zone is within said external zone, wherein said first and second paraboloids have parallel axes including a spacing between said parallel axes, said spacing equal to Kλ, wherein K is an integer greater than zero and λ is the wavelength of radiation to be received.

Claim 23

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a reflector having at least two sectors of paraboloids, wherein respective axes of the paraboloids of the at least two sectors extend in a same direction with said at least two sectors having different focal points, and with the foci of said at least two sectors offset by a spacing equal to a whole number of wavelengths of the radiation of a predetermined wavelength to be received, said reflector having a quasi-flat structure with respect to a direction along said axes, said antenna further including a respective source for each of the at least two sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources merged with the respective axes of the at least two sectors of paraboloids, said sources respectively adapted for reception of differently polarized radiation; and wherein a first of said sectors is a sector of a first paraboloid, said first paraboloid forming a central zone, and the second of said sectors is a sector of a second paraboloid, said second paraboloid forming an external zone, and wherein said central zone is within said external zone, wherein said first and second paraboloids have parallel axes including a spacing between said parallel axes, said spacing equal to Kλ, wherein K is an integer greater than zero and λ is the wavelength of radiation to be received.

Claim 24

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a first plurality of sectors formed of a plurality of respective paraboloids forming a first family of paraboloids, wherein apices of the first family of paraboloids are offset by K,λ/2 with said first plurality of sectors focusing upon a first focal point, wherein K 1 is an integer greater than zero; a second plurality of sectors formed of a second plurality of paraboloids with said second plurality of paraboloids forming a second family of paraboloids having apices offset by K 2 λ/2 and with said second plurality of sectors focusing at a second focal point, wherein K 2 is an integer greater than zero and λ is the wavelength of radiation to be received; said antenna further including a respective source for each of the first and second plurality of sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources respectively adapted for reception of differently polarized radiations; wherein said first and second focal points are offset by a whole number of wavelengths of the radiation of a predetermined wavelength to be received, and wherein the axes of the first family of paraboloids and the axes of the second family of paraboloids extend in a same direction, with the multi-focal receiving antenna having a quasi-flat structure with respect to a direction along said axes.

Claim 25

A multi-focal receiving antenna for receiving radiation of a predetermined wavelength, said antenna having a single aiming direction for more than one satellite, the antenna comprising: a first plurality of sectors formed of a plurality of respective paraboloids forming a first family of paraboloids, wherein apices of the first family of paraboloids are offset by K,λ/2 with said first plurality of sectors focusing upon a first focal point, wherein K 1 is an integer greater than zero; a second plurality of sectors formed of a second plurality of paraboloids with said second plurality of paraboloids forming a second family of paraboloids having apices offset by K 2 λ/2 and with said second plurality of sectors focusing at a second focal point, wherein K 2 is an integer greater than zero and λ is the wavelength of radiation to be received; said antenna further including a respective source for each of the first and second plurality of sectors for coupling the radiation, said sources located in zones of concentration of the radiation to be received, said sources respectively adapted for reception of differently polarized radiations; wherein said first and second focal points are offset by a whole number of wavelengths of the radiation of a predetermined wavelength to be received, and wherein the axes of the first family of paraboloids and the axes of the second family of paraboloids extend in a same direction, with the multi-focal receiving antenna having a quasi-flat structure with respect to a direction along said axes.