In accordance with one or more embodiments, a communication device includes a dielectric antenna having a feed point and an aperture. A cable comprising a conductorless core is coupled to the feed point of the dielectric antenna. A transmitter is coupled to the cable and facilitates a transmission of first electromagnetic waves to the feed point of the dielectric antenna. The first electromagnetic waves are guided by the conductorless core and propagate along the conductorless core without requiring an electrical return path, and the first electromagnetic waves generate free-space wireless signals from the aperture of the antenna in accordance with a circularly polarized antenna beam pattern.

Embodiments of the invention include an integrated single-piece antenna feed and a turnstile circular polarizer suitable for use in a satellite communications system. One embodiment of the integrated single-piece antenna includes a circular waveguide input, a turnstile, a coaxial feed horn, subreflector and subreflector support. Alternative embodiments utilize symmetrically oriented struts with or without a coaxial subreflector support to physically support a subreflector.

A circularly polarized radiating element includes at least one excitation aperture for a wave that is linearly polarized with what is referred to as an excitation first polarization, a frequency selective surface and a metasurface comprising a two-dimensional and periodic array of metasurface cells, the excitation aperture opening onto the metasurface, the metasurface cells all being oriented identically with respect to the excitation polarization and configured to: reflect an incident wave having the excitation polarization in order to form a reflected wave polarized with the excitation polarization, and depolarize and reflect the incident wave in order to form a reflected wave polarized with the orthogonal polarization, having a phase difference substantially equal to 90 with respect to the reflected wave polarized with the excitation polarization, and having an amplitude substantially equal to the amplitude of a wave radiated by the frequency selective surface, generated from the reflected wave polarized with the excitation polarization.

Disclosed is a dual-mode antenna array system (DAAS) for directing and steering an antenna beam that includes an approximately square feed (ASF) waveguide, a plurality of first-mode directional couplers (FMDCs), a plurality of second-mode directional couplers (SMDCs), a plurality of first-mode radiating elements (FMREs), and a plurality of second-mode radiating elements (SMREs). The ASF waveguide includes a first ASF waveguide wall, a second ASF waveguide wall, an ASF waveguide length, a first-feed waveguide input at a first-end of the ASF feed waveguide, and a second-feed waveguide input at a second-end of the ASF feed waveguide. The plurality of FMDCs are on the first ASF waveguide wall and the plurality of SMDCs are on the second ASF waveguide wall. The plurality of FMREs are in signal communication with the plurality of FMDCs and the plurality of SMREs are in signal communication with the plurality of SMDCs.

The present invention relates to a polarization device (10) for a satellite telecommunications antenna (11) including at least one frequency selective layer (12) able to convert a linear polarization (E), including two components (Ex, Ey), into left circular polarization in a first transmission frequency band (Tx) and into right circular polarization in a second receiving frequency band (Rx) or vice versa, the phase shift between the two components (Ex, Ey) of the linear polarization (E) being included between 85 and 95 degrees, preferably 90 degrees in one of the frequency bands (Rx, Tx), and the phase shift between the two components (Ex, Ey) of the linear polarization (E) being included between +85 and +95 degrees, preferably +90 degrees in the other frequency band (Rx, Tx).

An ultra-wideband linear-to-circular polarizer is disclosed. In accordance with embodiments of the invention, the polarizer includes a plurality of cascaded waveplates having biaxial permittivity or cascaded anisotropic sheet impedances. Each waveplate/sheet has a principal axis rotated at different angles relative to an adjacent waveplate/sheet about a z-axis of a 3-dimensional x, y, z coordinate system. Each waveplate is composed of a unit cell of an artificial anisotropic dielectric. Each sheet impedance is composed of an anisotropic metallic pattern. The polarizer further includes impedance matching layers disposed adjacent the cascaded waveplates/sheets.

An ultra-wideband linear-to-circular polarizer is disclosed. In accordance with embodiments of the invention, the polarizer includes a plurality of cascaded waveplates having biaxial permittivity or cascaded anisotropic sheet impedances. Each waveplate/sheet has a principal axis rotated at different angles relative to an adjacent waveplate/sheet about a z-axis of a 3-dimensional x, y, z coordinate system. Each waveplate is composed of a unit cell of an artificial anisotropic dielectric. Each sheet impedance is composed of an anisotropic metallic pattern. The polarizer further includes impedance matching layers disposed adjacent the cascaded waveplates/sheets.

A linear-to-circular polarizer antenna is disclosed. In accordance with embodiments of the invention, the polarizer antenna includes an antenna operable to transmit and receive polarized signals and a linear-to-circular polarizer coupled to the antenna. The polarizer includes a plurality of cascaded elements, waveplates or anisotropic sheets, having biaxial permittivity. Each cascaded element has a principal axis rotated at different angles relative to an adjacent element about a z-axis of a 3-dimensional x, y, z coordinate system, and each element is composed of an artificial anisotropic dielectric. The polarizer further includes impedance matching layers disposed adjacent the cascaded elements.

A linear-to-circular polarizer antenna is disclosed. In accordance with embodiments of the invention, the polarizer antenna includes an antenna operable to transmit and receive polarized signals and a linear-to-circular polarizer coupled to the antenna. The polarizer includes a plurality of cascaded elements, waveplates or anisotropic sheets, having biaxial permittivity. Each cascaded element has a principal axis rotated at different angles relative to an adjacent element about a z-axis of a 3-dimensional x, y, z coordinate system, and each element is composed of an artificial anisotropic dielectric. The polarizer further includes impedance matching layers disposed adjacent the cascaded elements.

Radio-frequency component including several waveguide devices, for example antennas or polarizers, arranged in an array for transmitting and/or receiving electromagnetic signals. The radio-frequency component includes several ridges and each waveguide device includes: at least one inner wall; an upstream opening in the direction of propagation of the signals during emission; and a downstream opening in the direction of propagation of the emitting signals, linked to the upstream opening so that the emitting signals are transmitted from the upstream opening to the downstream opening. The arrangement of the ridges in the openings upstream of the radiofrequency component may be different from the arrangement of the ridges in the openings downstream of the radio-frequency component. The arrangement of ridges in the downstream openings of each waveguide device includes no more and no less than three ridges.