Abstract: A dual-mode polarizer for selectively switching between linear polarization and circular polarization includes a first meander-line polarizer, and a second meander-line polarizer spaced apart from the first meander-line polarizer to define a first gap therebetween. A first angular orientation between the first and second meander-line polarizers produces variably-oriented linear polarization of a signal passing through the first and second meander-line polarizers, and a second angular orientation between the first and second meander-line polarizers produces variably-oriented circular polarization of a signal passing through the first and second meander-line polarizers.

Abstract: A variable inclination continuous transverse stub (VICTS) antenna system includes a support structure, a plurality of VICTS antenna elements attached to the support structure, and a controller operatively coupled to the plurality of VICTS antenna elements, the controller configured to coherently combine signals through each of the plurality of VICTS antenna elements.

Abstract: Systems and methods for controlling pointing of a transmit antenna aperture of a phased array antenna are described herein. A modem may be configured to modulate carrier wave signals for transmission to an end target via the transmit antenna aperture. A transmit power level of the modem may be monitored, and pointing of the transmit antenna aperture may be adjusted based on the transmit power level. Additionally or alternatively, an indication of a carrier-to-noise level may be received, and pointing of the transmit antenna aperture may be adjusted based on the carrier-to-noise level.

Abstract: A system and method provide simultaneous dual polarization operation using a linearly-polarized planar antenna and a polarizer spaced apart from the linearly-polarized planar antenna, the polarizer including a first polarization state having primarily one of left-hand circular polarization (LHCP) or right-hand circular polarization (RHCP), and a third polarization state having linear polarization from which a combination of both LHCP and RHCP is simultaneously derived. The polarizer is placed in the first polarization state to at least one of transmit or receive a signal having primarily one of LHCP or RHCP, and the polarizer is placed in the third polarization state to simultaneously transmit and/or receive two different signals, where a first signal of the two different signals has primarily LHCP and a second signal of the two different signals has primarily RHCP.

Abstract: A system and method provide simultaneous dual polarization operation using a linearly-polarized planar antenna and a polarizer spaced apart from the linearly-polarized planar antenna, the polarizer including a first polarization state having primarily one of left-hand circular polarization (LHCP) or right-hand circular polarization (RHCP), and a third polarization state having linear polarization from which a combination of both LHCP and RHCP is simultaneously derived. The polarizer is placed in the first polarization state to at least one of transmit or receive a signal having primarily one of LHCP or RHCP, and the polarizer is placed in the third polarization state to simultaneously transmit and/or receive two different signals, where a first signal of the two different signals has primarily LHCP and a second signal of the two different signals has primarily RHCP.

Abstract: A dual-mode polarizer for selectively switching between linear polarization and circular polarization includes a first meander-line polarizer, and a second meander-line polarizer spaced apart from the first meander-line polarizer to define a first gap therebetween. A first angular orientation between the first and second meander-line polarizers produces variably-oriented linear polarization of a signal passing through the first and second meander-line polarizers, and a second angular orientation between the first and second meander-line polarizers produces variably-oriented circular polarization of a signal passing through the first and second meander-line polarizers.

Abstract: Systems and methods for controlling pointing of a transmit antenna aperture of a phased array antenna are described herein. A modem may be configured to modulate carrier wave signals for transmission to an end target via the transmit antenna aperture. A transmit power level of the modem may be monitored, and pointing of the transmit antenna aperture may be adjusted based on the transmit power level. Additionally or alternatively, an indication of a carrier-to-noise level may be received, and pointing of the transmit antenna aperture may be adjusted based on the carrier-to-noise level.

Abstract: A true-time-delay feed network for a continuous transverse stub antenna array includes a plurality of feed levels, each comprising one or more rails, the feed levels arranged in a spaced configuration. An open parallel plate region is defined between adjacent ones of the feed levels. The rails of the plurality of feed levels are arranged to form a power divider network unencumbered with septums or wall portions protruding into the open region.

Abstract: An antenna array employing continuous transverse stubs as radiating elements is disclosed. In an exemplary embodiment, the array includes an upper conductive plate structure comprising a set of continuous transverse stubs, and a lower conductive plate structure disposed in a spaced relationship relative to the upper plate structure. A rotation apparatus provides rotation between the upper plate structure and the lower plate structure.

Abstract: An antenna array employing continuous transverse stubs as radiating elements is disclosed. In an exemplary embodiment, the array includes an upper conductive plate structure comprising a set of continuous transverse stubs, and a lower conductive plate structure disposed in a spaced relationship relative to the upper plate structure. A rotation apparatus provides rotation between the upper plate structure and the lower plate structure.

Abstract: Methods of fabricating air-filed true-time-delay, continuous transverse stub array antenna. A plurality of extruded sections that are physically independent of one another are fabricated. The plurality of extruded sections are arranged in a predefined pattern defining the structure of the array antenna. Adjacent surfaces of the extruded sections form waveguides of the array antenna. The plurality of extruded sections are joined together at their respective ends to form the array antenna. The plurality of extruded sections may be joined using a plurality of end plates. The plurality of extruded sections and end plates may comprise metal or plastic. If the extruded sections are plastic, they are metallized 44 using a process such as vacuum deposition, electroless plating, or lamination during the extrusion process. The end plates are sealed to the extruded sections to form the array antenna structure.

Abstract: Methods of fabricating air-dielectric true-time-delay, continuous transverse stub array antenna. The first method uses conventional machining or molding techniques to fabricate layers of plastic with desired microwave circuit features. The plastic layers are then metalized, assembled (aligned) and joined together, such as by using ultrasonic welding techniques. Readily available metalization and ultrasonic welding techniques exist that may be used. The second method uses sheets of metal, into which microwave circuit features are fabricated, such as by machining. The layers are then assembled (aligned) and joined together, using one of several available processes, such as an inert gas, furnace brazing technique, for example.

Abstract: A true-time-delay corporate feed that minimizes both scan- and frequency-dependent variations in driving point impedance by realizing and exploiting a folded ensemble of intentionally mismatched E-plane tee junctions, E-plane steps, and E-plane bends that are used to form the antenna feed. A selected arrangement of E-plane tee junctions, E-plane steps, and E-plane bends are interconnected between a line-source interface that receives RF power and a plurality of line-source interfaces that couple the RF power to radiating stubs of a continuous transverse stub antenna array. The impedance of the individual mismatched components are set to be essentially constant and purely real, such that the feed network ensemble behaves as a multi-stage transformer, efficiently matching dissimilar radiator (load) and line-source (source) impedances over a broad range of operating frequencies and scan angles.

Abstract: A planar antenna radiating structure comprising an array of continuous transverse stubs having a stepped configuration arranged in a ground plane of a parallel-plate waveguide. Control of the complex reflection coefficient of the aperture of the radiating structure over a range of operating frequencies and scan angles is accomplished using parallel-plate waveguide modes through a choice of stub length(s), stub height(s), inter-stub spacings, parallel-plate separation and the properties of dielectric media used for the parallel-plate waveguide and stubs.

Abstract: Power dividing apparatus comprising a T-junction and an E-plane step transformer having a phase slope equal and opposite to the phase slope of the T-junction, so that the overall phase slope through the T-junction and E-plane step transformer is minimized over a wide range of frequencies.

Abstract: A planar array antenna having a switching matrix that couples an RF signal to two distributed ferrite scanning line feeds that feed a planar continuous transverse stub array antenna. The scanning line feeds couple RF energy to the antenna from opposite sides to form a total of four beams offset in space that each cover different angular scan sectors. The antenna has reduced complexity and lower design and production costs. The use of dual ferrite scanning line feeds, the switching matrix, and the continuous transverse stub antenna to obtain wide-angle scanning provides significantly improved performance. The present invention uses the two distributed ferrite scanning line feeds to obtain greater scan coverage at upper millimeter-wave frequencies, where realizable ferrite materials are less active and provide diminished scan capability. The scanning line feeds and planar array antenna may be designed so that the four scan sectors are contiguous, to increase the angular scan coverage of the antenna.

Abstract: A rectangular waveguide rotary joint that allows limited mechanical rotation of two rectangular waveguides around a common longitudinal axis. The joint comprises a first rectangular waveguide having a first waveguide flange and a second rectangular waveguide having a second waveguide flange, wherein the second waveguide flange is disposed adjacent to the first waveguide flange with an air gap disposed therebetween. An RF choke is formed in the waveguide flanges for reducing RF leakage caused by the air gap, and a low friction spacer system for separating the first and second waveguides to maintain relative alignment of the waveguides during rotation and maintain a substantially constant separation between the waveguides. The waveguide rotary joint provides for a low voltage standing wave ratio (VSWR) and low insertion loss exhibited over a +/-30 degree rotation range.

Abstract: An optical fiber having a conductive layer disposed therearound has sections removed therefrom that form gaps that expose the underlying optical fiber. Light manifolds are formed at each gap, such as are provided by Bragg gratings photoinduced in the core at each gap, and photoconductive material is disposed at each of the gaps. An opaque coating may optionally be disposed over the outside of the photoconductive material to ensure that it is activated by light propagating within the optical fiber. Light transmitted down the fiber may be controllably coupled output of the fiber at each of the gaps. The optical fiber thus provides multiple functions including electrical conductor, light manifold, and substrate on which the photoconductive material is deposited.

Abstract: Spatial thinning in no more than two dimensions is used in order to lower both the effective dielectric constant and the dielectric loss tangent of ferroelectric ceramics, while retaining a substantial fraction of their tunability. By not thinning in the third direction, along which the dc bias field is applied, the ferroelectric material maintains the connectivity between elements of the ferroelectric structure that is essential to retaining the tunability. Examples of one-dimensional structures (30) include small diameter columns (28, 32) of dielectric material embedded in a dielectric matrix (26, 34). Examples of two-dimensional structures (21) include square (22) and hexagonal (24) cells comprised of ferroelectric material filled with inert dielectric material or vice versa.

Abstract: A dielectric material is formed into a structure having two parallel broad surfaces with one or more raised integral portions extending transversely across at least one of the broad surfaces. The exterior is uniformly conductively coated resulting in a parallel plate waveguide having a continuous transverse stub element disposed adjacent one plate thereof. Purely reactive elements are formed by leaving the conductive coating on the terminus of the stub element, or by narrowing the terminus of the stub element. Radiating elements are formed when stub elements of moderate height are opened to free space. Radiating, coupling and/or reactive continuous transverse stub elements may be combined in a common parallel plate structure in order to form a variety of microwave, millimeter wave and quasi-optical components including integrated filters, couplers and antenna arrays.