Abstract: A transmitter or receiver can include a phased array antenna system in which multiple characteristics of a transmitted or received beam can be controlled electronically. For example, in embodiments that include a transmitter, dual outputs of N signal modifiers can be connected to orthogonal inputs of N dual-orthogonally polarized antenna elements. Each signal modifier can modify the amplitude and phase of a communications signal in two parallel signal paths to produce two signal components each of which is an amplitude-modified/phase-shifted version of the communication signal. Multiple characteristics of the combined beam can be simultaneously controlled by setting the amplitude and/or phase-shift parameter values in the dual signal paths in the signal modifiers to combined values that individually affect each of the multiple characteristics of the combined beam.

Abstract: A horn-reflector antenna for tracking the location of in-flight aircraft is provided. The antenna includes an upwardly-opening horn having a reflector attached thereto. The horn may have an asymmetric rectangular cross-section and comprise at least one upwardly and outwardly extending side wall. The reflector includes a reflecting surface that may have a generally hyperbolic paraboloid shape or saddle shape. The horn and reflector may be constructed from a polymer material in an injection molding process. The reflecting surface of the reflector and the inner surfaces of the horn may be coated with a reflective or conductive material, for example, a paint comprising sliver-plated copper particles. In use, the horn-reflector antenna may be adapted to rotate around the longitudinal axis of a stationary waveguide feed. As such, the antenna of the present invention can be adapted for operation without the use of a rotary joint or a slip ring.

Abstract: A radio frequency (RF) horn can include an interior surface with an inner geometry comprising irregular, aperiodic corrugations and/or undulations. The pattern of the inner geometry can excite higher order modes simultaneously in two RF signals each at a different frequency that combine with fundamental modes of the signals to produce substantially Gaussian profiles of the two signals at the output aperture of the horn. Even though the signals are at different frequencies, the illumination pattern of both signals on a reflector antenna at which the horn is directed can be substantially the same.

Abstract: Stepped radio frequency (RF) reflector antennas are disclosed in which an inner RF reflector is disposed in a central opening of at one or more annular RF reflectors. The RF reflecting surface of the inner RF reflector and the RF reflecting surface(s) of the one or more annular RF reflectors can be shaped and positioned relative to each other to have different focal lengths but nevertheless reflect an RF signal to the same focal plane. The depth of the inventive reflector antenna system can be less than the depth of prior art reflector antennas with a comparable RF aperture.

Abstract: A radio frequency (RF) coaxial horn can comprise an inner RF horn disposed inside a larger outer RF horn. An interior surface of the inner horn can comprise a pattern of irregular, aperiodic features that excite modes in first and second RF signals each at a different frequencies that produce substantially Gaussian beam profiles of the first and second signals at the output aperture of the inner horn. The waists of the beam profiles of the first and second signals can be outside the inner horn but inside the outer horn. An interior surface of the outer horn and/or an outer surface of the inner horn can similarly excite modes in a third RF signal at a frequency different than the first and second RF signals to produce a substantially Gaussian beam profile of the third signal at the output aperture of the outer horn. The waist of the beam profile of the third signal can be aligned with the waists of the beam profiles of the first and second signals.

Abstract: A compact tracking coupler includes a plurality of ridged waveguides arranged circumferentially around a circular waveguide wherein long sides of the ridged waveguides extend circumferentially and short sides of the ridged waveguides extend radially relative to the circular waveguide. The compact tracking coupler can be especially useful in a multi-band antenna feed.

Abstract: A phase shifter comprises a substrate, a ground plane formed on a first surface of the substrate, a support structure positioned on a second surface of the substrate opposite the first surface, three parallel, non-co-planar microstrip lines supported by the support structure above the second surface of the substrate, a ferrite element supported by the support structure between the second surface of the substrate and the three non-co-planar microstrip lines, and means for applying a magnetic field to the ferrite element.