David Y Cheng

US Patent:

6336612, Jan 8, 2002

Filed:

Feb 13, 2001

Appl. No.:

09/783862

Inventors:

Frank Taormina - El Segundo CA
Donald C.D. Chang - Thousand Oaks CA
Kar W. Yung - Torrance CA
David C. Cheng - Palos Verdes Estates CA
William W. Mayfield - Torrance CA
John Novak, III - West Hills CA
Arthur W. Wang - Cypress CA

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

B64G 100

US Classification:

244158R

Abstract:

A satellite communication system has a first deployment of a plurality of satellites deployed in a medium earth orbit and two later deployments of a plurality of satellites deployed in the medium earth orbit. The first deployment is spaced so that the second deployment may be easily deployed and interleaved into the first deployment. A ground terminal is used for communicating with the satellites in the first and second deployments.

US Patent:

6460808, Oct 8, 2002

Filed:

Oct 23, 2001

Appl. No.:

10/008675

Inventors:

Frank Taormina - El Segundo CA
Donald C. D. Chang - Thousands Oaks CA
Kar W. Yung - Torrance CA
David C. Cheng - Palos Verdes Estates CA
William W. Mayfield - Torrance CA
John Novak, III - West Hills CA
Arthur W. Wang - Cypress CA

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

B64G 100

US Classification:

244158R

Abstract:

A satellite communication system has a first deployment of a plurality of satellites deployed in a medium earth orbit and two later deployments of a plurality of satellites deployed in the medium earth orbit. The first deployment is spaced so that the second deployment may be easily deployed and interleaved into the first deployment. A ground terminal is used for communicating with the satellites in the first and second deployments.

US Patent:

6501941, Dec 31, 2002

Filed:

Nov 2, 1999

Appl. No.:

09/432440

Inventors:

Donald C. D. Chang - Thousand Oaks CA
Kar W. Yung - Torrance CA
David C. Cheng - Palos Verdes Estates CA
Urban A. Von Der Embse - Los Angeles CA
Frank A. Taormina - El Segundo CA
Ming U. Chang - Rancho Palos Verdes CA

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

H04B 7185

US Classification:

455 131, 455427

Abstract:

Methods for increasing the efficiency of satellite constellation operations are disclosed. The steps of the present invention comprise calculating the maximum number of communications signals that each satellite in the satellite constellation can generate, determining an operational constraint on each satellite, the operational constraint limiting the number of communications signals that each satellite can radiate substantially simultaneously, determining an operational space for each satellite wherein the operational space is defined using the operational constraint and the calculated number of signals, and using the operational space for each satellite in the constellation to determine the operational point for the constellation.

US Patent:

6606307, Aug 12, 2003

Filed:

Nov 2, 1999

Appl. No.:

09/432439

Inventors:

Donald C. D. Chang - Thousand Oaks CA
Kar W. Yung - Torrance CA
David C. Cheng - Palos Verdes Estates CA
Urban A. Von Der Embse - Los Angeles CA
Frank A. Taormina - El Segundo CA
Ming U. Chang - Rancho Palos Verdes CA

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

H04B 7185

US Classification:

370316, 455 121

Abstract:

Methods for operating a satellite constellation are disclosed that utilize spatial diversity and directional gain antennas at ground terminal locations to provide multiple data rate services on a single frequency channel. One method comprises receiving a signal at a first and second satellite in the satellite constellation from a first communications device. A communications channel at a first frequency from the first satellite is used to communicate with the first communications device. A signal from a second communications device is received only at the second satellite at the first frequency, and the second satellite is used to communicate with the second communications device at the first frequency without substantially interfering with the communications with the first communications device.

US Patent:

6643268, Nov 4, 2003

Filed:

Aug 23, 1999

Appl. No.:

09/379168

Inventors:

Kar W. Yung - Torrance CA
David C. Cheng - Palos Verdes Estates CA
Kenneth N. Gibson - Redondo Beach CA

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

H04L 1228

US Classification:

370254, 370216

Abstract:

A method ( ) for identifying re-routing path solutions for signals within a switch network ( ). The path solutions are subject to special constraints that provide the most desired solution for a user. The method applies an algorithm that works by transforming a global problem ( ) into many individual sub-problems ( ). The algorithm then solves the individual sub-problems ( ) systematically according to desired constraints until the global solution is met ( ). The method finds a unique state for each switch such that the overall requirements of the system are met.

US Patent:

6766987, Jul 27, 2004

Filed:

Aug 28, 2002

Appl. No.:

10/230424

Inventors:

Frank Taormina - El Segundo CA
Donald C. D. Chang - Thousand Oaks CA
Kar W. Yung - Torrance CA
David C. Cheng - Palos Verdes Estates CA
William W. Mayfield - Torrance CA
John Novak, III - West Hills CA
Arthur W. Wang - Cypress CA

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

B46G 100

US Classification:

244158R, 701226

Abstract:

A satellite communication system has a first deployment of a plurality of satellites deployed in a medium earth orbit and two later deployments of a plurality of satellites deployed in the medium earth orbit. The first deployment is spaced so that the second deployment may be easily deployed and interleaved into the first deployment. A ground terminal is used for communicating with the satellites in the first and second deployments.

US Patent:

6785553, Aug 31, 2004

Filed:

Apr 24, 2001

Appl. No.:

09/841110

Inventors:

Donald C. D. Chang - Thousand Oaks CA
Kar W. Yung - Torrance CA
David C. Cheng - Boston MA
Ming U. Chang - Rancho Palos Verdes CA
Frank A. Hagen - Palos Verdes Estates CA

Assignee:

The Directv Group, Inc. - El Segundo CA

International Classification:

H04Q 720

US Classification:

4554565, 4554566, 3423571, 34235714, 342358

Abstract:

A method and system for using two-way ranging navigation to accurately determine the location of a transponder platform above-Earth or a fixed or mobile target on the ground or on water. The two-way ranging navigation measurements are used as calibration references, thereby improving the positioning accuracy of GPS. The system includes GPS and a two-way ranging navigation system for taking position measurements of a target. A correction factor is determined as a function of the measurements and the GPS position is adjusted by the correction factor. The method for calibrating GPS using two-way ranging navigation involves taking a two-way ranging navigation measurement and a GPS measurement of a target, determining a correction factor as a function of the measurements, and correcting the GPS position by taking a second GPS measurement and adjusting it by the correction factor.

US Patent:

6807397, Oct 19, 2004

Filed:

Oct 3, 2002

Appl. No.:

10/264197

Inventors:

Donald C. D. Chang - Thousand Oaks CA
Kar W. Yung - Torrance CA
David C. Cheng - Palos Verdes Estates CA
Urban A. Von Der Embse - Los Angeles CA
Frank A. Taormina - El Segundo CA
Ming U. Chang - Rancho Palos Verdes CA

Assignee:

Hughes Electronics Corporation - El Segundo CA

International Classification:

H04B 7185

US Classification:

455 131, 455429

Abstract:

Methods for increasing the efficiency of satellite constellation operations are disclosed. The steps of the present invention comprise calculating the maximum number of communications signals that each satellite in the satellite constellation can generate, determining an operational constraint on each satellite, the operational constraint limiting the number of communications signals that each satellite can radiate substantially simultaneously, determining an operational space for each satellite wherein the operational space is defined using the operational constraint and the calculated number of signals, and using the operational space for each satellite in the constellation to determine the operational point for the constellation.