Hughes Aircraft Company

California Institute of Technology

Hrl Laboratories, LLC

USA As Represented by Secretary of the Navy

Hughes Electronics Corporation

William B Bridges

James H Schaffner

Adrian E Popa

Lee J Burrows

Robert R Hayes

Yongfang Zhang

William M Bruno

An impedance matching structure for a RF MEMS switch having at least one closeable RF contact in an RF line, the impedance matching structure comprising a protuberance in the RF line immediately adjacent the RF contact that forms one element of a capacitor, the other element of which is formed by the switch's ground plane.

RF MEMS switch with integrated impedance matching structure

An element card for an ultra-wideband array antenna is disclosed. The element card has one or more integrated antennas and can be designed to operate over multiple decades of bandwidth. The element card may be arranged as part of an array of element cards to achieve operation in multiple frequency bands.

Integrated ultra wideband element card for array antennas

Improvements in an electro-optic modulator with a segmented optical transmission network with a series of discrete electrodes for successive segments of the network include drivers at the output of a corporate feed into the modular transmission line. The penalty of &#x221a;N suffered from division of the input power is thus avoided. Respective modulating signals are supplied to the electrodes along the transmission lines whose lengths differ from each other, so that modulating signals arrive at their respective electrodes in synchronism with the propagation of an optical signal through the optical transmission network. The differential loss in the different feed line lengths in the corporate feed are compensated by adjusting the gains of the amplifiers or by incorporating additional attenuation in the legs of the corporate feed.

Corporate feed for 40 GHz modulators and method for use of the same

A method for fabricating titanium-indiffusion waveguides in optical modulators and other optical waveguide devices includes disposing titanium, strips in a waveguide pattern on the surface of a crystalline substrate, such as lithium niobate or lithium tantalate, and indiffusing the titanium atoms into the crystalline substrate by creating a flowing, wet deuterium oxide (DO) environment, raising the temperature in the DO environment to a temperature within the range of 900 degrees Celsius and 1100 degrees Celsius and maintaining the temperature for a period of time that will allow for the necessary indiffusion of titanium to occur within the crystal substrate. The Ti-indiffusion waveguides that result from performing the Ti-indiffusion process in a flowing, wet DO environment include crystalline substrates, such as lithium niobate or lithium tantalate, titanium strips disposed in a waveguide pattern on the crystalline substrate and a diffusion region resulting from high temperature processing in a flowing, wet DO environment.

Titanium-indiffusion waveguides and methods of fabrication

A method for fabricating titanium-indiffusion waveguides in optical modulators and other optical waveguide devices includes disposing titanium strips in a waveguide pattern on the surface of a crystalline substrate, such as lithium niobate or lithium tantalate, and indiffusing the titanium atoms into the crystalline substrate by creating a flowing, wet deuterium oxide (D O) environment, raising the temperature in the D O environment to a temperature within the range of 900 degrees Celsius and 1100 degrees Celsius and maintaining the temperature for a period of time that will allow for the necessary indiffusion of titanium to occur within the crystal substrate. The Ti-indiffusion waveguides that result from performing the Ti-indiffusion process in a flowing, wet D O environment include crystalline substrates, such as lithium niobate or lithium tantalate, titanium strips disposed in a waveguide pattern on the crystalline substrate and a diffusion region resulting from high temperature processing in a flowing, wet D O environment.

An antenna. The antenna includes a first dielectric antenna rod having a first dielectric constant. The first dielectric antenna rod is coupled to a first frequency transmission source for propagating first frequency band radiation from the first dielectric antenna rod into a medium having a medium dielectric constant. A second dielectric antenna rod is provided having a second dielectric constant. The second dielectric antenna rod is coupled to a second frequency transmission source for propagating second frequency band radiation from the second dielectric antenna rod into the medium. The first dielectric antenna rod is coaxially mounted within the second dielectric antenna rod. The first dielectric constant is greater than the second dielectric constant. The second dielectric constant is greater than the medium dielectric constant.

Coaxial dielectric rod antenna with multi-frequency collinear apertures

A low profile, receiving and/or transmitting antenna is adapted to be mounted onto an interior portion of a building or other structure to receive or transmit radiation through a first dielectric material, such as a window, associated with the building or other structure. The antenna includes a receiving/transmitting horn filled with a second dielectric material and a surface for mounting the antenna to the first dielectric material so that the horn is disposed at a particular angle with respect to a surface of the first dielectric material. A matching layer may be disposed between the first dielectric material and the second dielectric material to provide for a reflectionless match between the first and second dielectric materials.

Antenna and method for receiving or transmitting radiation through a

A circuit and method for actively stabilizing the DC bias voltages applied to passive sections of a linearized directional coupler modulator. A reference electrical signal is applied to the active section of a linearized directional coupler modulator, thereby modulating an input optical beam. An optical detector is used at the output end of the modulator to monitor the modulated optical beam. The output of the detector is sent to one or more synchronous detectors that select the one or more harmonic frequency components that one wants to suppress. The synchronous detector output is sent to a filter that converts the harmonic frequency component to a DC bias voltage, which is integrated and used to bias the passive section of the modulator. The resulting negative-feedback loop minimizes the magnitude of the particular harmonic that is selected by the filter. In a preferred embodiment, the present stabilization circuit is used to stabilize the bias voltages in a three-section linearized directional coupler modulator, resulting in a stable modulator with low second harmonic distortion and low third-order intermodulation distortion.

Bias stabilization circuit and method for a linearized directional

An all metal, microwave-pumped, waveguide CO.sub.2 laser includes a waveguide providing a vacuum envelope containing the CO.sub.2 gas having a longitudinal ridge extending at least partially across the width of the waveguide and extending along a length of the waveguide and a ceiling facing the ridge. The ridge and ceiling have horizontal surfaces facing one another which together function as an optical waveguide of the laser and define a longitudinal optically active region therebetween which, in the preferred embodiment, opens out into remaining portions of the waveguide along either side of said ridge. A pair of reflecting mirrors are located at each end of said optically active region and an antenna or ramped waveguide couples a microwave source into the waveguide.

Microwave-excited slab waveguide laser with all metal sealed cavity

An electro-optic modulator such as a Mach-Zehnder interferometer has a segmented optical transmission network with a series of discrete electrodes for successive segments of the network. Respective modulating signals are supplied to the electrodes along transmission lines whose lengths differ from each other, so that modulating signals applied to the inputs of the transmission lines arrive at their respective electrodes in synchronism with the propagation of an optical signal through the optical transmission network. The modulating transmission lines are disposed lateral to and generally coplanar with the optical transmission network, preferably on a separate substrate. The desired differential in transmission line lengths can be achieved by positioning the input ends of the transmission lines along an edge of the input substrate that is at a desired angle to the optical transmission network.

Broad band, low power electro-optic modulator apparatus and method with

An optical waveguide (34) is formed in a substrate (32) made of an electro-optic material. A plurality of stripline electrodes (36) are formed on the substrate (32) in spaced relation along the optical waveguide (34). A stripline antenna (38) is connected to the upstream end of each electrode (36). An electromagnetic waveguide (40) directs an electromagnetic signal to the antennas (38), which couple the electromagnetic signal to the electrodes (36). The electromagnetic signal propagates along the electrodes (36) and electro-optically modulates an optical signal propagating parallel thereto through the optical waveguide (34). The electromagnetic waveguide (40) may direct the electromagnetic signal through the substrate (32) to the antennas (38) at an angle with the optical waveguide (34) selected to cause the electromagnetic signal to propagate through the substrate (32) in such a direction that the phase velocity of the electromagnetic wave along the direction of the optical waveguide (34) is substantially equal to the phase velocity of the optical signal propagating through the optical waveguide (34). Alternatively, the substrate (32') may be dimensioned to constitute the electromagnetic waveguide such that the electromagnetic signal propagates therethrough parallel to the optical waveguide (34) at the same phase velocity as the optical signal. The electromagnetic waveguide may also be provided as a separate dielectric waveguide (62) which extends parallel to the optical waveguide (34). An optical waveguide (94) may be split into two branches (94c, 94d) to enable amplitude modulation of the optical signal.

Antenna-fed electro-optic modulator

An electro-optic modulator (10) includes a pair of optical waveguide channels (20, 22) formed in an X-cut lithium niobate substrate (12) and an overlying RF coplanar waveguide (36). A periodic electrode structure (48) of the intermittent interaction type employs a plurality of middle stubs (52) to maintain the phase of the RF drive frequency in phase with the optical signal. The modulator (10) also utilizes shorter stubs (64) and tapered inlets (42) and outlets (44) to match and transform impedances.

Electro-optic modulator

An improved coupled waveguide laser array which provides a set of in-phase, phase locked optical beams is disclosed herein. The improved laser array of the present invention includes first and second coupled cavities for providing first and second beams in a first direction, respectively. The first and second cavities have substantially parallel longitudinal axes and apertures at first ends thereof for emitting the first and second beams. A mirror is mounted in a plane transverse to the longitudinal cavity axes and includes a first partially transmissive section mounted in optical alignment with the first cavity. The mirror further includes a first substantially reflective section mounted in optical alignment with the second cavity.

Coupled waveguide laser array

A flexible low-loss dielectric waveguide is made from a flexible low-dielectric constant hollow cylinder filled with high-dielectric constant powder. Alternatively, a rigid or semi-rigid waveguide comprises a groove formed in a low-dielectric constant substrate filled with high-dielectric constant powder.

Growing community of inventors

Sierra Madre, CA, United States of America

William B Bridges