Jeffrey C Adams

US Patent:

6483621, Nov 19, 2002

Filed:

Jul 28, 2000

Appl. No.:

09/627819

Inventors:

Jeffrey C. Adams - Seattle WA
Mark Pratt - Seattle WA
Micah J. Barclay - Redmond WA

Assignee:

Terabeam Corporation - Kirkland WA

International Classification:

H04B 1000

US Classification:

359159, 359181, 359189, 359193

Abstract:

A transmitted light signal, such as laser light, is modulated by a data signal and by a tracking signal. The tracking signal has a modulation depth that is substantially smaller than a peak-to-peak amplitude of the light signal. At reception, the tracking signal is recovered from the modulated light signal and is used to determine an orientation of a receiver with respect to the transmitted light signal.

US Patent:

6490070, Dec 3, 2002

Filed:

Jul 28, 2000

Appl. No.:

09/627279

Inventors:

Jeffrey C. Adams - Seattle WA
Mark Pratt - Seattle WA
Micah J. Barclay - Redmond WA

Assignee:

Terabeam Corporation - Kirkland WA

International Classification:

H04B 1000

US Classification:

359156, 359154, 359155, 359159, 359172, 359181

Abstract:

A polarization of a light signal is modulated to provide polarization tracking in a wireless optical communication system. The light signal having the modulated polarization, such as a sinusoidally varying polarization, is transmitted from an optical transmitter having polarization-maintaining fiber. The light signal having the modulated polarization is received at an optical receiver. A portion of the light signal is directed to an analyzer that detects the modulated polarization and generates an amplitude-modulated light signal corresponding to the modulated polarization. The amplitude-modulated light signal is directed to a tracking detector, such as a quad cell detector, that generates an amplitude-modulated electronic signal corresponding to the amplitude-modulated light signal. The amplitude-modulated electronic signal can be subsequently used to control or perform tracking of the optical receiver. Such tracking can include adjustment of an orientation of the optical receiver with respect to the light signal received from the transmitter.

US Patent:

6603554, Aug 5, 2003

Filed:

Dec 22, 2000

Appl. No.:

09/746122

Inventors:

Eric C. Eisenberg - Redmond WA
Shaun C. Hampton - Klamath Falls OR
Jeffrey C. Adams - Seattle WA
David P. Bajorins - Redmond WA

Assignee:

Terabeam Corporation - Kirkland WA

International Classification:

G01N 1159

US Classification:

356434, 3562391

Abstract:

An apparatus and method determines light transmission through a window. The window may be a single-pane or a double-pane window, and may or may not have coatings on its interior/exterior surfaces. Light transmission through the window can be measured based on power levels of light incident on the window and light reflected from the window. Such measurements can be performed for a wireless optical telecommunication system, in situations where it may be difficult or impossible to access both sides of a window to place or retrieve measurement equipment.

US Patent:

6941076, Sep 6, 2005

Filed:

May 16, 2001

Appl. No.:

09/859339

Inventors:

Jeffrey C. Adams - Seattle WA, US
Rand W. Lee - Kirkland WA, US

Assignee:

Terabeam Corporation - Falls Church VA

International Classification:

H04B010/00
H04B010/04
H04B010/12

US Classification:

398130, 398183, 398185, 398118

Abstract:

Systems and methods for the transmission of auxiliary data via a modulated carrier signal superimposed on a primary data communication signal between terminals of a free-space optical communication system are disclosed. The carrier signal is modulated with an auxiliary data signal via phase-shift keying, amplitude-shift keying, frequency-shift keying, or other suitable modulation technique, and superimposed on the primary data communication signal prior to transmission as an optical signal by a transmitting free-space optical terminal. The primary data communication signal is received by at least one photo detector coupled to a receiving free-space optical terminal that demodulates the primary data communication signal to reconstruct the auxiliary data.

US Patent:

20030095302, May 22, 2003

Filed:

Jun 23, 2001

Appl. No.:

09/888244

Inventors:

John Schuster - Bellevue WA, US
Jeffrey Adams - Seattle WA, US
John Bell - Issaquah WA, US
Gerald Tourgee - Convent Station NJ, US

International Classification:

H04J014/00
H04B010/00
H01S003/00
G02F002/00
G02F001/00

US Classification:

359/109000

Abstract:

An optical communication system is provided that has a network including a transmitter station that conveys data through a wireless pathway to a receiver station. An obstruction of the pathway is determined by measuring the attenuation of an optical beam arriving at or intending to arrive at a target receiver station and comparing the value with the attenuation of other optical beam(s) arriving at or intending to arrive at one or more reference receiving stations in the optical communication system. The values are interpreted to determine the nature of the blockage and various parameters in the optical data transmission system controlled according to the presence of a local blockage or global blockage. A further consideration in determining the type of blockage may be through measuring the backscattering of the optical beam. In addition, other aspects of the present invention relating to the storage and transfer of selected transaction data are described.

US Patent:

55086250, Apr 16, 1996

Filed:

Jun 23, 1994

Appl. No.:

8/264400

Inventors:

Jeffrey C. Adams - Renton WA

Assignee:

The Boeing Company - Seattle WA

International Classification:

G01R 2708

US Classification:

324702

Abstract:

The invention provides a way to improve the voltage stand-off characteristics of photoconductors, including both surface and bulk photoconductors. In a preferred embodiment, the invention comprises a photoconductor device having a semiconductor substrate with electrodes thereon, and a light source which illuminates the surface of the device in a pattern which is configured to increase the stand-off voltage of the device. A method according to the invention includes the steps of directing light onto the surface of the photoconductor thereby forming an illuminated area thereon, measuring the current draw of the photoconductor, and moving the illuminated area along the surface of the photoconductor until the current draw is minimized.