Sri International

Electro Scientific Industries, Inc.

David A Watt

Phillip Andrew Porras

Mark Alan Unrath

Michael G Corr

Steven Mark Dawson

Jesse Wodin

John Peter Marcotullio

David Manseau

Ronald E Pelrine

Brian W Baird

Mehmet Emin Alpay

Hisashi Matsumoto

Richard S Harris

Glenn Simenson

William J Jordens

Jay Johnson

Weisheng Lei

Mark F Schutzer

Robert M Pailthorp

John T Wen

John J Buonocore

Jan E Van Der Laan

Lindsey M Dotson

Robert H Sparr

Steven Chen

Eric Lavelle

Joseph M Strus

Leon Tao

Michael Tyler

Justin D Landrum

Jacob M Cooper

Boskin Erkocevic

Robert W Colby

Sunil Goda

Jeffrey W Leonard

Joshua A Arndt

Cris E Hill

Laura H Campbell

Roman Y Novoselov

Ben Potsaid

Systems and methods for clock synchronization are disclosed. A client synchronization system (CSS) may transmit RF pulses to a server CSS over micrometeorite ionization trail (MMIT) channels, and may receive RF pulses from the server CSS over MMIT channels, each received RF pulse following transmitted RF pulse. The client CSS may receive from the server CSS over MMIT channels measurement data including pulse arrival times at the server CSS. The measurement and transmission data may be correlated to identify RF-pulse pairs, each pairing a transmitted RF pulse received by the server CSS with a received RF pulse received from the server CSS, both over the same MMIT. TWTT analysis may be applied to timing data the pairs to compute time offsets between a client clock and a server clock. An analytical model of clock drift may be applied to the offsets to synchronize the client clock to the server clock.

Precision two-way time transfer over meteorburst communications channels

Implementation of radio frequency applications in satellite environments can be constrained by size, mass, cost, and power limitations. These applications can include radar, communications, radio astronomy, or other scientific or industrial applications. A variety of systems are provided to facilitate recording of baseband radio frequency signals at high bandwidth and low power using low-cost components. These systems include field-programmable gate arrays or other programmable logic devices integrating between high-frequency ADCs and two or more multiplexed non-volatile storage mediums. Also provided are systems for providing calibration and self-test functionality in a low-cost, flexible, low-power radio frequency frontend. These systems include high-frequency switches configured to allow a calibration and/or self-test pulse to be acquired for each radar pulse generated by the system.

CubeSat radar systems

Example gravity gradiometers are described that utilize high precision resonant optical cavities to measure changes in gravitational forces at high sensitivities. In one example, a sensing system includes a gravity gradiometer and a controller. The gravity gradiometer includes a first mirror and a second mirror arranged to form an optical cavity having an optical axis. The controller is configured to detect, responsive to displacement of at least one of the first mirror and the second mirror along the optical axis, a change in gravity gradient.

Compact and highly sensitive gravity gradiometer

A method and system increase processed specimen yield in the laser processing of target material that includes multiple specimens formed on a common substrate. Preferred embodiments implement a feature that enables storage in the laser processing system a list of defective specimens that have somehow been subject to error during laser processing. Once the common substrate has been completely processed, the system alerts an operator to the number of improperly processed specimens and gives the operator an opportunity to run a software routine, which in a preferred embodiment uses a laser to scribe a mark on the top surface of each improperly processed specimen.

Tracking and marking specimens having defects formed during laser via drilling

In one embodiment, the present invention is a method and apparatus for identifying wireless transmitters. In one embodiment, a method for identifying a transmitter in a wireless computing network includes extracting one or more radio frequency signal characteristics from a communication from the transmitter and generating a fingerprint of the transmitter in accordance at least one of the extracted radio frequency signal characteristics.

Method and apparatus for identifying wireless transmitters

In one embodiment, the present invention is a method and apparatus for wireless network security. In one embodiment, a method for securing a wireless computing network includes receiving a communication from an unidentified transmitter, identifying the transmitter in accordance with a fingerprint generated from one or more radio frequency signal characteristics extracted from the communication, and taking action in response to an identity of the transmitter.

Method and apparatus for wireless network security

Preferred embodiments of the invention implement techniques for modifying the command trajectory, the architecture of a servomechanism control system, or both, to reduce the servo error during and/or after the command trajectory. An iterative refinement procedure generates for use by the servomechanism control system a corrective input, du, which significantly reduces the error between the desired and actual servomechanism control system outputs. In one embodiment, a uniquely identified plant model is employed in the iterative refinement procedure to compute an approximate gradient that improves the performance and reliability of the refinement procedure. In another embodiment, the actual plant response is used in place of the identified model in the iterative refinement procedure. This is accomplished by time-reversing the stored error signal from a training run, before applying it to the plant to generate an update to the corrective input signal du.

Adaptive command filtering for servomechanism control systems

High speed removal of material from a specimen employs a beam positioner for directing a laser beam axis along various circular and spiral laser tool patterns. A preferred method of material removal entails causing relative movement between the axis of the beam and the specimen, directing the beam axis at an entry segment acceleration and along an entry trajectory to an entry position within the specimen at which laser beam pulse emissions are initiated, moving the beam axis at a circular perimeter acceleration within the specimen to remove material along a circular segment of the specimen, and setting the entry segment acceleration to less than twice the circular perimeter acceleration.

Methods for processing holes by moving precisely timed laser pulses in circular and spiral trajectories

Digital control of frequency and/or amplitude modulation techniques of an intracavity and/or extracavity AOM () facilitate substantially full extinction of a laser beam () to prevent unwanted laser energy from impinging a workpiece (); facilitate laser pulse amplitude stability through closed-loop control of pulse-to-pulse laser energy; facilitate beam-positioning control including, but not limited to, closed-loop control for applications such as alignment error correction, beam walk rectification, or tertiary positioning; and facilitate employment of more than one transducer on an AOM () to perform any of the above-listed applications.

AOM frequency and amplitude modulation techniques for facilitating full beam extinction in laser systems

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Newark, CA, United States of America

David A Watt