Northrop Grumman Systems Corporation

King Fahd University of Petroleum and Minerals

Center for Remote Sensing, Inc.

Raj Mittra

David L Richardson

Suman Ganguly

Farooq Sultan

Yoonjae Lee

Sheikh Sharif Iqbal Mitu

Leonard J Kuskowski

The ferrite-loaded, Fabry-Perot Cavity antenna uses a novel superstrate based beam scanning/shaping mechanism by optimally placing three magnetized ferrite cylinders within the cavity. Beam scan in a certain direction required oppositely located ferrite cylinder to be axially biased using externally controlled DC magnetizing field. The FPC utilizes a composite dielectric superstrate to inversely relate the mainlobe-to-sidelobe ratio with scan-angle, which demonstrates larger reduction in side lobe level with increases angle of beam scan. The designed 10 GHz ferrite-loaded FPC antenna has dimensions of 6.4 cm&#xd7;2 cm&#xd7;1.6 cm. It achieves a &#x2212;10 dB impedance bandwidth of 525 MHz, directivity of 11.04 dB and a broadside beam steering range of &#xb1;12&#xb0; for 200 kA/m (0.25 T) changes in the externally applied axial magnetizing field.

Ferrite-loaded, Fabry-Perot cavity antenna

A multifrequency antenna comprising a stack of nonconductive substantially planar substrates, with a conductive layer disposed on each substrate surface. A first substrate includes transmission lines disposed on a rear surface and a conducting layer on the other surface. A second substrate is stacked on the first substrate. A conducting layer is disposed on one side of the second substrate surface. Conducting layers disposed on first and second substrates include a plurality of slotted openings arrayed about an antenna axis. A third substrate stacked on the second substrate includes a conducting layer top. A lossy dielectric-magnetic material encloses sides and rear of the multifrequency antenna, to prevent electromagnetic energy penetration through the enclosure. An edge diffraction suppresser reflector is attached in the rear surface of the multifrequency antenna, and has two or more essentially circular, conducting plates and a multitude of conducting cylinders along the axis of the multifrequency antenna.

Multifrequency antenna with reduced rear radiation and reception

A collision avoidance system for a vehicle has a vehicle steering sensor for sensing a direction in which the vehicle is being steered, a source of radiation, an articulated reflector for directing radiation from the source in a desired direction, an articulation mechanism for effecting articulation of the articulate reflector, and a close loop control circuit responsive to the vehicle steering sensor for controlling the articulation mechanism so as to cause the articulated reflector to direct radiation in a direction which is generally the same as that direction in which the vehicle is turning.

Vehicle collision avoidance system

Growing community of inventors

State College, PA, United States of America

Raj Mittra