Raytheon Company

Other

Jeffrey C Upton

Jack J Schuss

Kaichiang Chang

Richard L O'Shea

Thomas V Sikina

Eli Brookner

Michael G Sarcione

Angelo M Puzella

Jerome D Hanfling

Kassam K Bellahrossi

Frank G Cipolla

Edward A Geyh

William J Payne

Arsenio Vargas

John R Mather

Steven D Nguyen

Barry VanWyck

Described is a calibration technique for an Active Electronically Scanned Array (AESA) having a scalable, analog monopulse network.

Calibration system and technique for a scalable, analog monopulse network

Methods and apparatus for a phased array radar system including an array comprising columns of super-elements containing radiator elements located along a length of the super-element, wherein the super-elements form the columns such that super-elements are arranged end-to-end, wherein the super-elements are arranged in the column at randomized locations to reduce sidelobes. In a further embodiment, super element lengths can be randomized.

Method and apparatus for reducing sidelobes in large phased array radar with super-elements

Methods and apparatus for a super-element assembly for a phased array radar aperture, the super-element assembly having a first port and a second port to receive a first signal at the first port to generate a main beam, and receive a second signal at the second port to generate an image beam for generating scan volume coverage using the main and image beams.

Methods and apparatus for volumetric coverage with image beam super-elements

Methods and apparatus for a calibration system including a support structure movable over an array, a super-element secured to the support structure to obtain information at selected locations in relation to the array, and a processor to compute a sum of voltages for determining a level of calibration for the array.

Calibration of large phased arrays using fourier gauge

An array antenna system for forming multiple independently steered beams is described. The antenna system includes series or parallel feed circuits and phase shifters which are not disclosed directly in the signal path between the feed circuits and antenna elements included in the array antenna system.

Array antenna having multiple independently steered beams

A low array antenna having transmit/receive (T/R) modules, which contain a digitally-controlled variable attenuator, for each of the two polarizations (horizontal and vertical). The array has a cylindrically curved surface which closely conforms to the shape of the fuselage of an airborne vehicle or another structure. Each polarization feeds into an elevation beamformer apparatus which provides both a uniform taper and a Bayliss/Taylor taper. As the beam is scanned in elevation, the amplitude taper is adjusted via the variable attenuator to control the taper of a sum pattern and thereby achieve low sidelobe far field sum patterns. The same attenuators that are used for the sum pattern also feed a difference network. The T/R module attenuators are set to yield the desired low sidelobe sum illumination for a desired elevation scan angle. As the array is steered in elevation, the Bayliss difference taper is distorted since the fixed elevation beamformer cannot adjust the difference pattern for the new scan angle. A T/R module is provided at each column of the array to combine the distorted Bayliss difference pattern with the compensated Taylor sum pattern output. This combining permits the distorted Bayliss array illumination to be resymmetrized thereby producing a high quality, low sidelobe, compensated Bayliss far field pattern. This apparatus provides for complete compensation of both sum and difference patterns with only a single attenuator at each element of the array and a simple monopulse feed network.

Scan compensation for array antenna on a curved surface

A radar type center fed antenna comprising a small radiating horn supported at the focal point of a parabolic reflector by three struts which are oriented to minimize the parallel polarization scattering and which have a low scattering ogive cross-section. The horn is mounted at the vertex of the parabolic surface and the intersection of the three struts using a bracket that provides minimal blockage. The struts are attached to the perimeter of the reflector. One strut having a feed waveguide is attached to the top-center of the reflector and the other two are attached at points on either side of the bottom-center at thirty degree angles to the vertical plane. The strut shape and feed-horn supporting and attaching arrangement and the integration of the feed waveguide into one of the struts results in a very low sidelobe antenna that produces a far-field pattern that has very low forward scattering due to feed and strut blockage.

Low sidelobes antenna

A multiple band antenna feed used with parabolic reflector antennas and the like. The feed is arranged as two coaxially disposed waveguides. A planar array of patch elements is disposed at the end of the coaxial waveguides so the energy in each band radiates from a common phase center. This simplifies the arrangement of associated subreflectors.

Growing community of inventors

Groton, MA, United States of America

Jeffrey C Upton