Abstract:
In order to calibrate a transmitter and/or receiver for controlling a beam-forming network, the control signals are each divided into a plurality of frequency segments. The control signals are multiplexed per frequency segment with complex coefficients such that the transmitter output signals, after passing through a reference receiver, correspond in each case with the corresponding control signals. Corresponding compensation is carried out in the reception direction. The invention enables the same beam characteristics to be set for the transmitter and the receiver, without highly accurate transmitters and receivers being necessary.
Abstract:
The structure includes at least one substrate (2) of dielectric material, at least one face of which carries an orderly and geometrically periodic array of elements of electrically conductive material or, in a converse manner, bears at least one layer (3) of conductive material having an orderly and geometrically periodic array of holes (4). The structure is characterised in that control means (5, 6; 7) are associated with the substrate (2) of dielectric material for varying the dielectric or magnetic constant of the material so as correspondingly to modify its passband.
Abstract:
According to various embodiments, systems and methods for beamforming feed waves. An apparatus can include a reconfigurable arrangement of a first beamforming component and a second beamforming component. The first beamforming component can be configured to convert feed waves from a feed source into one or more intermediate beam patterns. The second beamforming component can be configured to convert the one or more intermediate beam patterns received at the second beamforming component from the first beamforming component into one or more output beam patterns based on one or more beamforming component configuration states of the reconfigurable arrangement.
Abstract:
An antenna system for a global navigation satellite system reference base station is disclosed. The antenna system includes an antenna positioned above a high capacitive impedance surface (HCIS) ground plane. Over a specific range of the lateral dimension of the HCIS ground plane and the height of the antenna above the HCIS ground plane, a high level of multipath suppression and high sensitivity for low-elevated satellites can be simultaneously maintained. The HCIS ground plane can be fabricated as a flat conducting plate with an array of conducting elements such as pins, pins with expanded tips, or mushroom structures. Alternatively, the HCIS can be fabricated as a flat conducting plate with a concentric series of choke rings. The antenna system can provide a positioning accuracy of +/-1 mm, an order of magnitude improvement over previous designs.
Abstract:
A reconfigurable aperture (200) includes a plurality of metallic particles (220) confined to a volume (216) extending across an aperture area. The metallic particles are repositioned within the volume to form opaque regions in the aperture area. The opaque regions, and transmissive regions between the opaque regions, can form a reconfigurable zone plate that can change the collimation of a microwave beam via diffraction therethrough. The zone plate can be located a fixed distance away from a microwave source and a detector in a housing, so that for any specified wavelength produced by the microwave source, the zone plate can reconfigure to have a focal length equal to the fixed distance. The reconfigurable zone plate can effectively collimate microwaves produced by the microwave source, can direct the collimated microwaves in a specified direction, can receive microwaves returning along the specified direction, and can focus the received microwaves onto the detector.