Coaxial tracking signal coupler for antenna feed horn

Claim 2

An antenna system comprising: a beam steering system, a feed horn, a waveguide transmission line connected to said feed horn, a coaxial coupler mounted at the juncture of said waveguide and said horn, said coupler containing elements responsive to nonaxial horn signal components, said horn and waveguide being adapted to operate on TE11 signal energy, said non-axial components comprising a TE01 component when the departure from the axis is perpendicular to the polarization of said signal and a TM01 component when the departure from the axis is parallel to the polarization of said signal, said coupler including a plurality of longitudinal irises responsive to said TE01 signal, said irises being located at the end of the coupler extending into said horn, said coupler also including an axial coupling probe responsive to said TM01 signal components and extending along the axis of and in direction of said waveguide, and means for utilizing said non-axial components to operate said steering system to reduce said non-axial components.

Claim 3

In an antenna of the type designed to receive both communications and beacon signals from a satellite, wherein said antenna includes means responsive to said beacon signals which, through the agency of antenna control servomechanisms, orient said antenna to track said satellite, said antenna including a horn section and a waveguide feed section, the improvement comprising: a coaxial coupler mounted at the juncture of said horn and said waveguide, said coaxial coupler including means extending into the throat of said horn section for converting TM01 horn signal components to TEM signal components, and means connected to said coupler for extracting said TEM signal components, said components being used to establish signals for operating said servomechanisms.

Claim 4

In an antenna of the type designed to receive both communications and beacon signals from a satellite, wherein said antenna includes means responsive to said beacon signals which, through the agency of antenna control servomechanisms, orient said antenna to track said satellite, said antenna including a horn section and a waveguide feed section, the improvement comprising: a coaxial coupler mounted at the juncture of said horn and said waveguide, said coaxial coupler including means extending into the throat of said horn section for converting TM01 horn signal components to TEM signal components, and means connected to said coupler for extracting said TEM signal components, said components being used to establish signals for operating said servomechanisms.

Claim 5

The improvement of claim 2 wherein said coupler is tapered at both ends to minimize signal transmission discontinuities.

Claim 6

The improvement of claim 2 wherein said means for extracting said TEM signal components includes an elongated probe oriented axially with respect to said waveguide feed section, said probe being connected to the center conductor of a coaxial cable passing through the interior of said coupler and through the wall of said waveguide feed section.

Claim 7

An antenna for use in a satellite communications and tracking ground station where the satellite to be tracked transmits communications signals at one frequency and beacon signals at a second frequency, said antenna comprising a horn section to receive both said signals and a waveguide section coupled to said horn section for transmitting received signals to signal utilization means, a coaxial coupler mounted within said horn and waveguide sections at the juncture thereof, one portion of said coaxial coupler extending coaxially into the throat of said horn and another portion of said coaxial coupler extending coaxially into said waveguide, the transverse external dimensions of said coupler being sufficiently small compared to the internal transverse dimensions of said waveguide that no substantial interference with transmission of the TE11 fundamental mode from said horn to said waveguide occurs at any communication frequency, said coaxial coupler including means in the horn thereof for converting TM01 horn signal components of said beacon signals into TEM signal components, coaxial line means connected to said coaxial coupler and extending through a wall of said antenna, said coaxial line means providing a TEM output separate from the TE11 output of said antenna, and means in the horn portion thereof for extracting TE01 horn signal components and coupling them to a second coaxial line means providing a TE01 output separate from the TE11 output of said antenna.

Claim 8

An antenna for use in a satellite communications and tracking ground station where the satellite to be tracked transmits communications signals at one frequency and beacon signals at a second frequency, said antenna comprising a horn section to receive both said signals and a waveguide section coupled to said horn section for transmitting received signals to signal utilization means, a coaxial coupler mounted within said horn and waveguide sections at the juncture thereof, one portion of said coaxial coupler extending coaxially into the throat of said horn and another portion of said coaxial coupler extending coaxially into said waveguide, the transverse external dimensions of said coupler being sufficiently small compared to the internal transverse dimensions of said waveguide that no substantial interference with transmission of the TE11 fundamental mode from said horn to said waveguide occurs at any communication frequency, said coaxial coupler including means in the horn thereof for converting TM01 horn signal components of said beacon signals into TEM signal components, coaxial line means connected to said coaxial coupler and extending through a wall of said antenna, said coaxial line means providing a TEM output separate from the TE11 output of said antenna, and means in the horn portion thereof for extracting TE01 horn signal components and coupling them to a second coaxial line means providing a TE01 output separate from the TE11 output of said antenna.

Claim 9

A receiving antenna comprising a horn section, a waveguide section, and a coupler mounted coaxially in the throat of said antenna at the juncture of said horn and said waveguide, said horn and waveguide being adapted to operate on TE11 signal energy and to produce in response to non-axial components TE01 and TM01 signal energy, said coupler having elements responsive to said non-axial horn signal components and comprising an elongated substantially cylindrical conductive member having a diameter small compared to the cross-section of said waveguide and wherein both ends of said coupler are tapered.

Claim 10

A receiving antenna comprising a horn section, a waveguide section, and a coupler mounted coaxially in the throat of said antenna at the juncture of said horn and said waveguide, said horn and waveguide being adapted to operate on TE11 signal energy and to produce in response to non-axial components TE01 and TM01 signal energy, said coupler having elements responsive to said non-axial horn signal components and comprising an elongated substantially cylindrical conductive member having a diameter small compared to the cross-section of said waveguide and wherein both ends of said coupler are tapered.

Claim 11

The antenna of claim 6 wherein a portion of said coupler extends into the throat of said horn and contains longitudinal irises responsive to said TE01 signal energy.

Claim 12

The antenna of claim 6 wherein a portion of said coupler extends along said waveguide and terminates in an axial probe responsive to said TM01 signal energy.