Abstract:
An apparatus and method for mitigating polarization mismatch in reflector antenna systems. A feed unit is configured to determine a polarization mismatch between a first polarization associated with a first wave and a second polarization associated with a reflector unit. The feed unit pre-distorts the first wave to achieve a compensated polarization for reducing and/or eliminating a polarization mismatch. The pre-distorted first wave having the compensated polarization is used to illuminate the reflector unit. A re-radiated wave is reflected by the reflector unit. Furthermore, the level of the re-radiated wave is increased as a result of the pre-distortion.
Abstract:
Systems and methods are provided for separating the uplink signal from the downlink signal in a satellite communication system. A communication terminal for satellite communications is provided, comprising a reflector having a prime focus; a first feed located at the prime focus of the reflector and in optical communication with the reflector; a frequency-selective surface module having a reflected focus and located at a point along a communication path between the main reflector and the first feed; and a second feed located at the reflected focus of the frequency- selective surface module and in optical communication with the frequency-selective surface module.
Abstract:
An integral waveguide device herein includes a polarizer component comprising a waveguide and a dielectric slab, the dielectric slab configured to change a polarization of a signal passing through the waveguide. The integral waveguide device also includes a feed hom for conveying signals between the waveguide and a parabolic antenna. The waveguide of the polarizer and the feed hom are manufactured as an integral component with the feed hom disposed at a first end of the waveguide.
Abstract:
An integrated waveguide for use in high radio frequency communication is provided. The integrated waveguide including: a first substrate including a first plastic layer having on a first inward-facing surface, a first portion of a waveguide feature formed on the first inward-facing surface, and a metal layer disposed on the first inward-facing surface; and a second substrate including a second plastic layer having a second inward-facing surface, a second portion of a waveguide feature formed on the second inward-facing surface, and a metal layer disposed on the second inward-facing surface, wherein the first substrate and the second substrate are assembled to define an integrated waveguide feature defined by an assembling of the first portion of the waveguide feature and the second portion of the waveguide feature.
Abstract:
A hybrid scanning antenna including: a reflector having a focal line; a first mechanical movement to move the reflector about a first axis; a second mechanical movement to move the reflector about a second axis; a linear array fixedly disposed along the focal line to electronically scan at a scan angle about a third axis; and a controller to control the first mechanical movement, the second mechanical movement and the scan angle of the linear array to orient the hybrid scanning antenna to a look angle of a remote transceiver.
Abstract:
A system for reducing antenna spillover in a satellite communications system is disclosed. The system may include an apparatus comprising an antenna terminal, which in turn may include a sub-reflector and a main reflector. The main reflector may include at least one of an extension, a shroud, and a serrated edge. The extension may be a full rim extension or a partial extension. The shroud may be a full shroud or a partial shroud. The serrated edge may include a straight serration or a curved serration, the serrated edge also having various dimensions and profiles. In some examples, the sub-reflector and the main reflector of the antenna terminal may be provided and configured to reduce antenna spillover in accordance with antenna performance and interference restrictions set forth by one or more governing bodies.
Abstract:
A method for providing frequency selective surface zoning includes selecting a location for positioning a frequency selective surface (FSS) panel along a support arm of a reflector antenna system, and positioning a second feed horn on the support arm on an opposite side of the FSS panel. A number of unit cells are used to populate the FSS panel, and metallic patterns are formed on each unit cell. Multiple zones are subsequently defined on the surface of the FSS panel. Each zone is optimized for a predetermined range of incident angles.
Abstract:
A system and method for tracking non-geo synchronous orbit satellites on orbiting planes of regular motion patterns. The method includes providing a first satellites moving in a direction descending in latitude in first orbital planes and a second satellites moving in a direction ascending in latitude in second orbital planes; steering an antenna to an antenna tilt φ from normal with a single axis mechanism lined up with a first axis; scanning, electronically, with a linear array at a scan angle ψ along a second axis; and locking to a signal from a handed-from satellite from the first satellites, where the first axis is angled from the second axis, the steering along the first axis and the scanning along the second axis jointly track the handed-from satellite. A handoff between the first satellites may use one of the second satellites as a steppingstone.
Abstract:
Various antenna systems are presented that have independently steerable receive and transmit beams. The antenna system may include multiple antenna element systems. Each antenna element system may include multiple phase shifters that alter the phase of received signals and signals to be transmitted. Directions of a first transmit beam, a second transmit beam, a first receive beam, and a second receive beam may be steered independently using the phase shifters. Each antenna element system may include a polarization system.
Abstract:
A digital phase shifter is described where each bit of the phase shifter has a circuit block including one PIN diode in parallel with one transmission line. The phase shifter requires only one PIN diode and one transmission line per bit circuit block. Each PIN diode behaves like a simple switch for phase shifting. When the PIN diode is forward biased ("on" state), current flows through the PIN diode and the RF signal is not phase shifted. When the pin diode is not forward biased ("off" state), current flows through the transmission line parallel to the PIN diode and the RF signal is phase shifted by the transmission line. The digital phase shifter may have n circuit blocks in series, and adjacent PIN diodes may share a current when both are on. The phase shifter may be implemented in a phased array or reflect array antenna including multiple phase shifters.