Westinghouse Electric Corporation

Northrop Grumman Systems Corporation

US Government As Represented by the Secretary of the Army

Lawrence E Dickens

Douglas W Maki

Harvey C Nathanson

Robert Miles Young

Frank A Lindberg

Howard N Fudem

Dale E Dawson

Philip C Smith

David Krafcsik

Soong H Lee

Paul H Mountcastle

R Chris Clarke

Gregory DeSalvo

Don E Crockett

Anthony L Conti

Fred E Sacks

Gary F Shade

A MEMS switch having spaced-apart RF conductors on a substrate with a bridge structure disposed above the substrate. In one embodiment the bridge structure has two flexible arms supported by two support members and in another embodiment the bridge structure has three flexible arms supported by three support members, the third support member being electrically integral with the second conductor. The bridge structure is drawn down to effect electrical contact between the first and second conductors by application of a control signal to a control electrode, having an opposed electrode on the undersurface of the bridge structure. A central stiffener portion of the bridge prevents any contact between the control and opposed electrodes.

Microelectromechanical RF switch

A solid state microwave switch having a plurality of adjacent parallel fingers covered with an oxide layer. One end of a finger is an N&plus; source region while the other end is an N&plus; drain region, with a current conducting N region between them. The oxide layer is covered with a gate layer to which a gate signal is applied for control of current between the N&plus; regions through the N region. The gate layer is highly resistive and has a sheet resistance on the order of millions of ohms per square. The length from the source to drain region is around 2 &mgr;m, and the fingers are spaced with a pitch of around 1 &mgr;m.

Solid state RF switch with high cutoff frequency

A reflective hybrid analog phase shifter is detailed which is operable in the X-band, and which exhibits minimal phase shift variation with higher power loadings. A pair of back-to-back connected Schottky varactor diodes are serially connected to each of the phase shifting ports of a 3 dB coupler. The Scottky varactor diodes are reverse biased to permit continuous variation of the phase shift as a function of analog bias potential. A monolithically fabricated implementation of this circuit design is detailed.

Wide band microwave analog phase shifter

A loosely coupled microstrip microwave coupler with high directivity is disclosed. The coupler comprises a ground plane substrate, a dielectric layer disposed over the substrate, and a section of each of the main and coupled transmission lines disposed on the exposed surface of the dielectric layer adjacently aligned with a predetermined gap therebetween to form a coupling region. The length of the coupling region is substantially less than 1/4 wavelength of the operating microwave signal. A capacitive coupling element is disposed within the coupling region across the main and coupled transmission line sections for supplementing the dielectric capacitive coupling of the gap therebetween to increase the directivity of the microwave signal coupling. The capacitive coupling element splits the coupled transmission line section of the coupling region into two branches and is physically adjustable in size to balance the electric and magnetic field microwave coupling components of one of the branches to reduce the microwave power output thereof. As a result, the microwave power output of the other of the branches is representative of the microwave signal incident on the main transmission line section substantially.

Microwave coupler with high isolation and high directivity

Disclosed is a means for obtaining a high Q oscillator which is compact and s adapted to be readily incorporated into known forms of microwave integrated circuits, e.g. a parametric amplifier. The oscillator which for example may comprise a pump oscillator for a parametric amplifier includes efficient means for coupling to microstrip without destroying the high Q of the oscillator circuit. The negative resistance elements which may be, for example, a Gunn diode, IMPATT diode or the like is located in a resonator cavity which is a combination of radial transmission line cavity and a rectangular waveguide cavity.

Microwave oscillator for microwave integrated circuit applications

The tuned elements of a mixer organization are fabricated as slot-type microwave integrated circuit (MIC) elements formed by selected masking or etching of a continuous ground plane layer of conductor material on one side of an integrated circuit dielectric substrate, and of the discrete strips and other geometric forms affixed to the other side of the substrate. A pair of longitudinally aligned coplanar strip transmission line sections with an intermediate short longitudinally aligned slot transmission line section therebetween form hybrid junctions containing balanced diode modulation circuits where such coplanar lines and the slot line are joined. A strip line unit formed on the other side of the substrate is the input port for the RF input signal and is configured to provide a microstrip line-slot line transition at the midpoint of the slot line, feeding the RF input signal to both hybrid junctions with the same phase. The LO input signal is applied to the respective coplanar strip line sections with a constant phase difference therebetween of 90.degree.. This is conveniently provided by a quadrature hybrid. The IF outputs from the coplanar lines have a 90.degree. difference in phase and are received and summed by opposite and isolated ports of another quadrature hybrid to provide a common phase output IF signal.

Image phased and idler frequency controlled mixer formed on an

A field effect pentode transistor, which provides a gain over an extremely broad band of frequencies is disclosed. The transistor has source and drain electrodes defined by ohmic contacts, a first gate input control electrode defined by a Schottky-barrier, a screen electrode, and a second control gate Schottky-barrier electrode. The screen electrode is an ohmic contact located between the first and second gate control electrodes; and the second control electrode is located between the screen electrode and the drain electrode.

Field effect pentode transistor

A balanced microwave diode mixing circuit utilizes the junction of a slot transmission line and a coplanar strip transmission line as the point of diode modulation to provide heterodyne mixing. By the use of slot line type elements formed on one side of a dielectric substrate and strip line type elements formed on the other side, the following features are achieved: (A) input of the local oscillator (LO) signal and output of the intermediate frequency (I.F.) signal are achieved through a common coupling to and from the coplanar strip line at the end of the latter which is remote from the hybrid junction; (B) low reactance at the 'sum frequency' is presented at the hybrid junction; (C) low reactance at the image frequency is presented at the hybrid junction; and (D) high impedance at the input signal frequency is presented at the hybrid junction.

Growing community of inventors

Baltimore, MD, United States of America

Lawrence E Dickens