175 results about "Feed horn" patented technology

A method of and apparatus for beam steering. A feed horn is arranged so that the feed horn illuminates a tunable impedance surface comprising a plurality of individually tunable resonator cells, each resonator element having a reactance tunable by a tuning element associated therewith. The tuning elements associated with the tunable impedance surface are adjusted so that the resonances of the individually tunable resonator cells are varied in a sequence and the resonances of the individually tunable resonator cells are set to values which improve transmission of information via the tunable impedance surface and the feed horn.

A low-profile antenna system includes a main reflector (102) formed as a shaped main reflector surface that is approximately, but not precisely, parabolic. The main reflector (102) has a main reflector edge configuration (103) that is asymmetric. A feed system (104) for the main reflector includes a subreflector (106) formed as a shaped subreflector surface that is approximately, but not precisely, elliptical. The subreflector has a subreflector edge configuration (107) that is also asymmetric. An RF feed horn (108) associated with the feed system 104 has an aperture profile which also has an asymmetric shape.

A multiple mode feed horn is provided for transmitting and receiving signals. The feed horn includes a transverse electric throat section, a transverse electric profile section, and a transverse electric aperture section. The transverse electric profile section propagates a first transverse electric (TE) mode. The transverse electric aperture section propagates a second TE mode. The multiple mode feed horn prevents propagation of traverse magnetic modes from said throat section to said aperture section.

The present invention provides an improved single antenna system that allows reception of RF energy at multiple frequencies. In one embodiment, the antenna is implemented as a multi-beam, multi-feed antenna having a primary reflector fitted with a dual mode feed tube and a switchable LNB that supports both Ka band and Ku band reception. In another embodiment, the antenna is implemented as a multi-beam, multi-feed antenna having a primary reflector fitted with a feed horn and a LNB that is capable of providing movement such that the feed horn with the LNB is at a focal point with the primary reflector for both Ka and Ku band reception. In another embodiment, the antennae is implemented as a multi-beam, multi-feed antenna having a primary reflected fitted with a feed horn assembly and a switchable LNB that supports both Ka band and Ku band reception.

The present invention provides an improved antenna system on moving platform that is in communication with multiple satellites for simultaneous reception and transmission of RF energy at multiple frequencies. The antenna is implemented as a multi-beam, multi-band antenna having a main reflector with multiple feed horns and a sub-reflector having a reflective surface defining an image focus for a Ka band frequency signal and a prime focus for a Ku band frequency signal.

Scanning apparatus which may be used in a real-time passive millimeter wavelength imaging system or in other radiometry systems. The apparatus scans input radiation from a scene and output radiation is transmitted to a receiver system, for example a millimeter wave imaging camera or a radar receiver. The apparatus comprises a rotatable reflective plate having an axis of rotation passing through the centre of its surface and a lens arrangement for selectively transmitting and focusing radiation having a particular direction of polarisation. The apparatus may also comprise a feed horn array comprising a plurality of feed horns, the feed horns forming part of a spherical surface having a radius of curvature substantially equal to R/2 and being concentric with the third substantially spherical polarising element. The apparatus may further comprise a detector array comprising a plurality of detector elements. The detector array may form part of a millimeter wave imaging camera.

A method of manufacturing a cellular reflectarray antenna arranged in an m by n matrix of radiating elements for communication with a satellite includes steps of determining a delay φm,n for each of said m by n matrix of elements of said cellular reflectarray antenna using sub-steps of: determining the longitude and latitude of operation, determining elevation and azimuth angles of the reflectarray with respect to the satellite and converting theta₀ (θ₀) and phi₀ (φ₀), determining Δβ_m,n, the pointing vector correction, for a given inter-element spacing and wavelength, determining Δφ_m,n, the spherical wave front correction factor, for a given radius from the central element and/or from measured data from the feed horn; and, determining a delay φm,n for each of said m by n matrix of elements as a function of Δβ_m,n and Δφ_m,n..

A feed horn and systems and methods of making and using the feed horn are presented. Exemplary feed horns include a first portion comprising a dual mode geometry and a second portion comprising an axial corrugation geometry. The feed horn may operate simultaneously in a plurality of separate frequency bands (e.g., from about 18.3 GHz to about 20.2 GHz and from about 29.1 GHz to about 30.0 GHz) and a plurality of separate waveguide modes (e.g., TE₁₁, TM₁₁ or HE₁₁ modes); simultaneously operating over two bandwidth segments of at least 1900 MHz that are separated by at least 5000 MHz. The feed horn may have a short axial length (e.g. less than 4 wavelengths at 18.3 GHz), and it may be configured to operate in a prime fed offset reflector antenna system. In addition, the feed horn may be formed as a single piece via a single casting pull.

Various aspects of the disclosure provide low index metamaterials. The low index metamaterials may be used to form soft and/or hard electromagnetic (EM) boundaries to facilitate desired EM performance or propagation in applications including feed horns, spatial feed/combiners, isolation barriers between antennas or RF modules, and reduced radar cross-section applications. In one aspect, a low index metamaterial comprises a dielectric layer and a plurality of conductors on a surface of the dielectric layer, embedded in the dielectric layer or both, wherein the low index metamaterial appears as a medium having a dielectric constant less than one with respect to electromagnetic waves at predetermined frequencies and propagating at grazing angles with respect to a surface of the low index metamaterial.

More reliable satellite television reception in moisture conditions is provided by recognizing the critical relationship between satellite signal transmissivity and the effects of superhydrophobocity. Instead of trying to use a hydrophobic or superhydrophobic coating or material to shed water from a satellite antenna, superhydrophobic materials and coatings are strategically utilized to minimize the impact of water on the transmissivity of the satellite signal through transmissive surfaces in the antenna system. In a preferred embodiment, an exterior surface of a feed horn cover is coated with a superhydrophobic material to maintain a more consistent satellite signal reception. In an alternate embodiment, an exterior surface of a dome covering a small dish DBS satellite television antenna system is coated with a superhydrophobic material to minimize the overall satellite signal loss during moisture conditions so as to permit a dome to be effectively used over a small dish DBS satellite television antenna system.

A lens-based millimeter wave transceiver for use in wireless communication systems operating in the E-band spectrum consistent with the FCC rules regulating the 71-76 GHz and 81-86 GHz bands. The transceiver includes a single lens adapted for transmission of millimeter radiation to form communication beams in one band of either a band of about 71-76 GHz or a band of 81-86 GHz and for collection and focusing of millimeter wave radiation from communication beams in the other of the two bands. It includes a feed horn adapted to broadcast millimeter radiation through said single lens and to collect incoming millimeter wave radiation collected and focused by said single lens. A millimeter wave diplexer separates incoming and outgoing millimeter wave radiation.

The present invention provides a feed horn for use in an antenna assembly having a non-circular reflector. The feed horn is capable of transmitting and receiving circularly polarized signals. The feed horn includes a circular waveguide section for connection to a transmitter and receiver of the antenna assembly. A conical waveguide section is connected to an opposed end of the circular waveguide section for creating a smooth transition from the circular waveguide section to a non-circular corrugated waveguide section. The corrugated waveguide section includes a plurality of corrugations that transition for a circular shape adjacent to the conical waveguide section to an increasing non-circular shape at an end proximal to the reflector of the antenna assembly. The corrugations have individuals depths defined in the inner wall of the corrugated waveguide section. These depths compensate circularly polarized signals propagating in the feed horn for distortions due to the non-circular reflector.

A modular waveguide feed horn is provided that includes an assembly having a waveguide plate section. The modular waveguide feed horn assembly also includes a feed horn section having at least one feed horn. The feed horn section is separately provided from and removably coupled to the waveguide plate section.

A feed assembly for an antenna having a non-circular reflector, in which the feed assembly includes a feed horn capable of correcting the distortions of circularly polarized signals caused by the non-circular reflector profile, and wherein the feed horn is coupled with a polarizer that is field-switchable between linear and circular polarization modes of operation. The feed assembly can include a second receive-only feed located in close proximity to the feed horn for communication with adjacent satellites.

A relatively low cost, easy to install and aesthetically pleasing multi-band, multi-port digital video broadcast from satellite (DVBS) elliptical horn antenna designed as part of a reflector antenna system to simultaneously receive satellite television broadcast signals with circular polarity on two frequency channels. This type antenna may be implemented with a single antenna feed horn with multiple feed horns that may be arranged separately or in one or more integral feed horn blocks. The antennas may be designed to achieve acceptable circular polarity performance over broad and multiple frequency bands through the use of oppositely sloped differential phase differential sections.

This invention is a compact and cost effective signal receiver for use in conjunction with a parabolic reflector to receive electromagnetic signals from two satellites. The signal receiver has a dual elliptical corrugated feed horn to increase C/N ratio and reduce the spill over loss of the energy of signals receiving from two satellites, and to provide a sufficient rejection for preventing interference coming from the other satellite.

A miniature dual-band two-way mobile satellite-tracking antenna system mounted on a movable vehicle includes a miniature parabolic reflector dish having an elliptical aperture with major and minor elliptical axes aligned horizontally and vertically, respectively, to maximize azimuthal directionality and minimize elevational directionality to an extent corresponding to expected pitch excursions of the movable ground vehicle. A feed-horn has a back end and an open front end facing the reflector dish and has vertical side walls opening out from the back end to the front end at a lesser horn angle and horizontal top and bottom walls opening out from the back end to the front end at a greater horn angle. An RF circuit couples two different signal bands between the feed-horn and the user. An antenna attitude controller maintains an antenna azimuth direction relative to the satellite by rotating it in azimuth in response to sensed yaw motions of the movable ground vehicle so as to compensate for the yaw motions to within a pointing error angle. The controller sinusoidally dithers the antenna through a small azimuth dither angle greater than the pointing error angle while sensing a signal from the satellite received at the reflector dish, and deduces the pointing angle error from dither-induced fluctuations in the received signal.

An electronically scanned antenna may include a plurality of space-fed, contiguous subarrays arranged in an annular region, each subarray including an inner set of radiating elements facing inwardly, an outer-facing set of radiating elements, and a feed system for illuminating the inner set of radiating elements. A plurality of RF amplifiers are coupled through a commutation switch matrix to selected ones of the subarray feed horn systems to illuminate a desired sector with RF energy.