David W Chambers

US Patent:

6984210, Jan 10, 2006

Filed:

Dec 18, 2002

Appl. No.:

10/323467

Inventors:

David H. Chambers - Livermore CA, US
Jeffrey Mast - Loveland CO, US
Stephen G. Azevedo - Livermore CA, US
Frank Wuebbeling - Billerbeck, DE
Frank Natterer - Muenster, DE
Neb Duric - Albuquerque NM, US
Peter J. Littrup - Bloomfield MI, US
Earle Holsapple - Grosse Pointe Farms MI, US

Assignee:

Barbara Ann Karmanos Cancer Institute - Detroit MI

International Classification:

A61B 8/00

US Classification:

600443

Abstract:

A method and apparatus are provided for investigating tissue in which acoustic data are derived from scattering a plurality of pulsed spherical or cylindrical acoustic waves from a plurality of transmission elements through the tissue to a plurality of receiving elements. The acoustic data, which include a mix of reflected and transmitted acoustic waves, are received and digitized, and a representation of a portion of the tissue is generated from the digitized acoustic data.

US Patent:

7463690, Dec 9, 2008

Filed:

Nov 10, 2005

Appl. No.:

11/271334

Inventors:

James V. Candy - Danville CA, US
David H. Chambers - Livermore CA, US
Brian L. Guidry - Tracy CA, US
Andrew J. Poggio - Livermore CA, US
Christopher L. Robbins - Livermore CA, US

Assignee:

Lawrence Livermore National Security, LLC - Livermore CA

International Classification:

H04L 27/00

US Classification:

375259, 375346

Abstract:

A communication system for transmitting a signal through a channel medium comprising digitizing the signal, time-reversing the digitized signal, and transmitting the signal through the channel medium. In one embodiment a transmitter is adapted to transmit the signal, a multiplicity of receivers are adapted to receive the signal, a digitizer digitizes the signal, and a time-reversal signal processor is adapted to time-reverse the digitized signal. An embodiment of the present invention includes multi bit implementations. Another embodiment of the present invention includes 1-bit implementations. Another embodiment of the present invention includes a multiplicity of receivers used in the step of transmitting the signal through the channel medium.

US Patent:

8482452, Jul 9, 2013

Filed:

Aug 26, 2011

Appl. No.:

13/219475

Inventors:

David H. Chambers - Livermore CA, US
Jeffrey E. Mast - Loveland CO, US
David W. Paglieroni - Pleasanton CA, US
N. Reginald Beer - Pleasanton CA, US

Assignee:

Lawrence Livermore National Security, LLC - Livermore CA

International Classification:

G01S 13/90

US Classification:

342 22, 342 25 R, 342 25 F

Abstract:

A method and system for detecting the presence of subsurface objects within a medium is provided. In some embodiments, the imaging and detection system operates in a multistatic mode to collect radar return signals generated by an array of transceiver antenna pairs that is positioned across the surface and that travels down the surface. The imaging and detection system pre-processes the return signal to suppress certain undesirable effects. The imaging and detection system then generates synthetic aperture radar images from real aperture radar images generated from the pre-processed return signal. The imaging and detection system then post-processes the synthetic aperture radar images to improve detection of subsurface objects. The imaging and detection system identifies peaks in the energy levels of the post-processed image frame, which indicates the presence of a subsurface object.

US Patent:

8207886, Jun 26, 2012

Filed:

Sep 11, 2009

Appl. No.:

12/557546

Inventors:

David H Chambers - Livermore CA, US
Sean K Lehman - Pleasanton CA, US
Dennis M Goodman - Danville CA, US

Assignee:

Lawrence Livermore National Security, LLC - Livermore CA

International Classification:

G01S 13/00

US Classification:

342 22, 342118

Abstract:

A model-based approach to estimating wall positions for a building is developed and tested using simulated data. It borrows two techniques from geophysical inversion problems, layer stripping and stacking, and combines them with a model-based estimation algorithm that minimizes the mean-square error between the predicted signal and the data. The technique is designed to process multiple looks from an ultra wideband radar array. The processed signal is time-gated and each section processed to detect the presence of a wall and estimate its position, thickness, and material parameters. The floor plan of a building is determined by moving the array around the outside of the building. In this paper we describe how the stacking and layer stripping algorithms are combined and show the results from a simple numerical example of three parallel walls.

US Patent:

20030028870, Feb 6, 2003

Filed:

Jan 25, 2002

Appl. No.:

10/056955

Inventors:

Mitchell Weisman - San Carlos CA, US
Anthony Martin - Los Altos CA, US
David Chambers - Elkins NH, US

International Classification:

G06F009/445

US Classification:

717/178000, 717/173000

Abstract:

In one embodiment, a first stage software is bundled together with a first downloadable software available from a first server computer. The first stage software includes computer instructions for downloading a second downloadable software available from a second server computer. When an end-user wishes to download the first downloadable software, the second downloadable software is also offered to the end-user. Accepting the offer results in the first stage software downloading the second downloadable software onto the end-user's client computer. In one embodiment, the second downloadable software is downloaded in chunks.

US Patent:

20040059265, Mar 25, 2004

Filed:

Sep 11, 2003

Appl. No.:

10/661249

Inventors:

James Candy - Danville CA, US
David Chambers - Livermore CA, US

Assignee:

The Regents of the University of California

International Classification:

A61H001/00

US Classification:

601/002000

Abstract:

Noninvasively focusing acoustical energy on a mass such as a tumor within tissue to reduce or eliminate the mass. The presence of the mass in the tissue is detected by applying acoustic energy to the substance. The mass is localized to determine its position. Temporal signatures are developed to drive the acoustical energy on the mass. Dynamic focusing of the acoustical energy on the mass to reduce or eliminate it is accomplished utilizing the temporal signatures.

US Patent:

20040167396, Aug 26, 2004

Filed:

Feb 25, 2003

Appl. No.:

10/374570

Inventors:

David Chambers - Livermore CA, US
Stephen Azevedo - Livermore CA, US
Jeffrey Mast - Loveland CO, US

Assignee:

The Regents of the University of California

International Classification:

A61B005/05

US Classification:

600/425000

Abstract:

A quantitative imaging method and system for surrounding a target region with a plurality of transducers such that an acoustic pulse transmitted from one of the transducers may be received as pulse-derived temporal data at the receiving transducers. A controller operably connects to the transducers for selecting different transmission locations around the target region from where acoustic pulses may be transmitted. A signal processor connected to the transducers operates to remove from the received pulse-derived data of each receiving transducer a record of the pulse directly transmitted to the receiving transducer. And the pulse-derived temporal data modified in this manner is used by the data processor to determine preliminary values for a compressibility term and a density term for each point of the target region. The preliminary values for the respective compressibility term and density term obtained from the different transmission locations, are then averaged by the data processor to ultimately produce quantitative image maps of compressibility and density of the target region.

US Patent:

20040243584, Dec 2, 2004

Filed:

Apr 2, 2004

Appl. No.:

10/816779

Inventors:

Christopher Wesley - Redwood City CA, US
Eric McKinlay - Cupertino CA, US
David Chambers - Elkins NH, US
Craig Zeldin - Redwood City CA, US
Mitchell Weisman - San Carlos CA, US
Mark Pennell - Austin TX, US

International Classification:

G06F007/00

US Classification:

707/010000

Abstract:

In one embodiment, a blocking layer prevents a client computer without a pass from accessing a website. The blocking layer may have opaque or transparent portions, and may prevent an end-user on the client computer from interacting with the website. The pass may comprise a cookie, for example. Depending on implementation, the client computer may still be provided temporary access to the website to minimize any negative effect the blocking layer may have on website traffic. The end-user may also be provided an offer to gain permanent access to the website.