US Government as Represented by the Secretary of the Army

Elmer Freibergs

Robert E Horn

Yu-Wen Y Chang

Harold Jacobs

Harold Jacobs, Deceased

Lothar Wandinger

A multi-mode, common-aperture antenna system capable of simultaneously transmitting and/or receiving electromagnetic radiation in at least two frequency bands. The antenna system includes a first beam antenna comprised of a parabolic reflector and four open-ended waveguides that act as an antenna feed. The parabolic reflector focuses radiation along a first beam axis that may be scanned electronically or mechanically. The four waveguides extend from the focus of the parabolic reflector to transceivers that transmit and/or receive radiation in a first mode. The transceivers mount at the rear of the reflector. The antenna system also includes a second beam antenna which operates in a second mode, e.g. optical or infrared (IR) mode. The second beam antenna includes a small opening in the parabolic reflector that acts as an optical aperture for a focusing lens mounted at the rear of the reflector and positioned coaxially with the small opening. An optical apparatus occupies the focal plane of the focusing lens. The optical apparatus generates and/or senses optical radiation incident with the beam axis of the second beam antenna.

Dual-mode, common-aperture antenna system

An integrated circuit tunable cavity oscillator for extremely high freque operation in image line waveguide. The oscillator includes a metal base with a cylindrical bore, a dielectric or semiconductor waveguide mounted atop the metal base and having a bore which is continuous with the metal base bore. A Gunn or IMPATT diode is assembled in the metal base bore on top of a drum which is urged upwards toward the waveguide bore by a spring located behind the drum. From above, cavity tuning means including a top disk and a threaded screw cover the waveguide bore and push the diode into the metal base bore to define the cavity height of the coaxial cavity of the oscillator. The waveform, which is set up in the recessed cavity in the metal base, is launched into the waveguide. Thus, a ruggedized, low cost, tunable (by a tuning screw) and low weight oscillator for millimeter wave image line or microstrip operation is obtained. Furthermore, the oscillator diode and cavity defining hardware are easily replaceable.

Integrated circuit tunable cavity oscillator

A millimeter wave line scanner is disclosed providing steered fan-shaped ms from opposite faces at substantially equal angles of a semiconductor waveguide, rectangular in cross section, and having a plurality of equally spaced metallic perturbations or strips disposed on one of the two radiating sides or faces. Different angles of scan are selectively obtained by means of at least one distributed longitudinal PIN diode formed on an adjoining side of the semiconductor waveguide having electrical circuit means coupled thereto for controlling the diode's conductivity which acts to change the guide wavelength and accordingly cause a variation in radiation angle of the two equal beams radiating from opposite faces. The waveguide with one or more PIN diodes may also be used as a phase shifter. To reduce losses, a dielectric insulating layer is disposed between each PIN diode and the waveguide, which prevents the propagation of the wave into the PIN diode.

Growing community of inventors

Toms River, NJ, United States of America

Elmer Freibergs