William C Cheng

US Patent:

6396428, May 28, 2002

Filed:

Jun 4, 2001

Appl. No.:

09/873897

Inventors:

William W. Cheng - Redondo Beach CA

Assignee:

Raytheon Company - Lexington MA

International Classification:

H03M 300

US Classification:

341143, 341155

Abstract:

A continuous time Bandpass Delta Sigma ( ) Modulator architecture with feedforward and feedback coefficients to completely specify both the signal transfer function (STF) and the noise transfer function (NTF) for a stable modulator ADC system.

US Patent:

6414615, Jul 2, 2002

Filed:

Mar 22, 2000

Appl. No.:

09/532626

Inventors:

William W. Cheng - Redondo Beach CA

Assignee:

Raytheon Company - Lexington MA

International Classification:

H03M 300

US Classification:

341143, 341144

Abstract:

A high-performance delta sigma analog-to-digital converter. The high-performance delta sigma analog-to-digital converter includes a first mechanism for converting an input analog signal to a digital output signal. The first mechanism is characterized by a transfer function that is altered relative to an ideal transfer function. A second mechanism compensates for the alteration in the transfer function via a single additional digital-to-analog converter. In a specific embodiment, the alteration includes an additional pole and an additional zero induced by feedback delays in the first mechanism. The feedback delays include signal dependent jitter delay and feedback digital-to-analog converter cell switching delays. The second mechanism includes an additional latch that compensates for the signal dependent jitter delay. The first mechanism includes a resonator and a quantizer.

US Patent:

6457076, Sep 24, 2002

Filed:

Sep 13, 2000

Appl. No.:

09/661117

Inventors:

William Cheng - San Gabriel CA
Kenneth Hwang - Los Angeles CA
Ravi Kannan - Los Angeles CA
Babu Katchapalayam - Los Angeles CA
Bing Liu - Alhambra CA
Balaji Narasimhan - Culver City CA
Gopal Ramanujam - Los Angeles CA
Jonathan Tran - Alhambra CA

Assignee:

Networks Associates Technology, Inc. - Santa Clara CA

International Classification:

G06F 1300

US Classification:

710 36, 709200, 709206, 709220, 709224, 714 25

Abstract:

A system and method update client computers of various end users with software updates for software products installed on the client computers, the software products manufacturered by diverse, unrelated software vendors. The system includes a service provider computer system, a number of client computers and software vendor computer systems communicating on a common network. The service provider computer system stores in an update database information about the software updates of the diverse software vendors, identifying the software products for which software updates are available, their location on the network at the various software vendor computer systems, information for identifying in the client computers the software products stored thereon, and information for determining for such products, which have software updates available. Users of the client computers connect to the service provider computer and obtain a current version of portions of the database. The client computer determines that software products stored thereon, and using this information, determines from the database, which products have updates available, based on product name and release information for the installed products.

US Patent:

6496875, Dec 17, 2002

Filed:

Apr 30, 2002

Appl. No.:

10/136266

Inventors:

William Cheng - San Gabriel CA
Kenneth Hwang - Los Angeles CA
Ravi Kannan - Los Angeles CA
Babu Katchapalayam - Los Angeles CA
Bing Liu - Alhambra CA
Balaji Narasimhan - Culver City CA
Gopal Ramanujam - Los Angeles CA
Jonathan Tran - Alhambra CA

Assignee:

Networks Associates Technology, Inc. - Santa Clara CA

International Classification:

G06F 300

US Classification:

710 1

Abstract:

A system and method update client computers of various end users with software updates for software products installed on the client computers, the software products manufacturered by diverse, unrelated software vendors. The system includes a service provider computer system, a number of client computers and software vendor computer systems communicating on a common network. The service provider computer system stores in an update database information about the software updates of the diverse software vendors, identifying the software products for which software updates are available, their location on the network at the various software vendor computer systems, information for identifying in the client computers the software products stored thereon, and information for determining for such products, which have software updates available. Users of the client computers connect to the service provider computer and obtain a current version of portions of the database. The client computer determines that software products stored thereon, and using this information, determines from the database, which products have updates available, based on product name and release information for the installed products.

US Patent:

6542943, Apr 1, 2003

Filed:

Apr 17, 2002

Appl. No.:

10/124909

Inventors:

William Cheng - San Gabriel CA
Kenneth Hwang - Los Angeles CA
Ravi Kannan - Los Angeles CA
Babu Katchapalayam - Los Angeles CA
Bing Liu - Alhambra CA
Balaji Narasimhan - Culver City CA
Gopal Ramanujam - Los Angeles CA
Jonathan Tran - Alhambra CA

Assignee:

Networks Associates Technology, Inc. - Santa Clara CA

International Classification:

G06F 1300

US Classification:

710 36, 709200, 709206, 709220, 709224, 714 25

Abstract:

A system and method update client computers of various end users with software updates for software products installed on the client computers, the software products manufacturered by diverse, unrelated software vendors. The system includes a service provider computer system, a number of client computers and software vendor computer systems communicating on a common network. The service provider computer system stores in an update database information about the software updates of the diverse software vendors, identifying the software products for which software updates are available, their location on the network at the various software vendor computer systems, information for identifying in the client computers the software products stored thereon, and information for determining for such products, which have software updates available. Users of the client computers connect to the service provider computer and obtain a current version of portions of the database. The client computer determines that software products stored thereon, and using this information, determines from the database, which products have updates available, based on product name and release information for the installed products.

US Patent:

6668289, Dec 23, 2003

Filed:

Oct 4, 2002

Appl. No.:

10/264670

Inventors:

William Cheng - San Gabriel CA
Kenneth Hwang - Los Angeles CA
Ravi Kannan - Los Angeles CA
Babu Katchapalayam - Los Angeles CA
Bing Liu - Alhambra CA
Balaji Narasimhan - Culver City CA
Gopal Ramanujam - Los Angeles CA
Jonathan Tran - Alhambra CA

Assignee:

Networks Associates Technology, Inc. - Santa Clara CA

International Classification:

G06F 1310

US Classification:

710 36, 709220, 709221, 709224, 709200, 709206, 714 25

Abstract:

A system and method update client computers of various end users with software updates for software products installed on the client computers, the software products manufacturered by diverse, unrelated software vendors. The system includes a service provider computer system, a number of client computers and software vendor computer systems communicating on a common network. The service provider computer system stores in an update database information about the software updates of the diverse software vendors, identifying the software products for which software updates are available, their location on the network at the various software vendor computer systems, information for identifying in the client computers the software products stored thereon, and information for determining for such products, which have software updates available. Users of the client computers connect to the service provider computer and obtain a current version of portions of the database. The client computer determines that software products stored thereon, and using this information, determines from the database, which products have updates available, based on product name and release information for the installed products.

US Patent:

6763403, Jul 13, 2004

Filed:

Apr 17, 2002

Appl. No.:

10/125276

Inventors:

William Cheng - San Gabriel CA
Kenneth Hwang - Los Angeles CA
Ravi Kannan - Los Angeles CA
Babu Katchapalayam - Los Angeles CA
Bing Liu - Alhambra CA
Balaji Narasimhan - Culver City CA
Gopal Ramanujam - Los Angeles CA
Jonathan Tran - Alhambra CA

Assignee:

Networks Associates Technology, Inc. - Santa Clara CA

International Classification:

G06F 1300

US Classification:

710 36, 709200, 709206, 709220, 709224, 714 25

Abstract:

A system and method update client computers of various end users with software updates for software products installed on the client computers, the software products manufacturered by diverse, unrelated software vendors. The system includes a service provider computer system, a number of client computers and software vendor computer systems communicating on a common network. The service provider computer system stores in an update database information about the software updates of the diverse software vendors, identifying the software products for which software updates are available, their location on the network at the various software vendor computer systems, information for identifying in the client computers the software products stored thereon, and information for determining for such products, which have software updates available. Users of the client computers connect to the service provider computer and obtain a current version of portions of the database. The client computer determines that software products stored thereon, and using this information, determines from the database, which products have updates available, based on product name and release information for the installed products.

US Patent:

6768442, Jul 27, 2004

Filed:

Oct 25, 2002

Appl. No.:

10/280680

Inventors:

Clifford W. Meyers - Rancho Palos Verdes CA
Lloyd F. Linder - Agoura Hills CA
Kenneth A. Essenwanger - Walnut CA
Don C. Devendorf - Carlsbad CA
Erick M. Hirata - Torrance CA
William W. Cheng - Redondo Beach CA

Assignee:

Raytheon Company - Lexington MA

International Classification:

H03M 136

US Classification:

341158, 341159, 327 65, 327 89

Abstract:

An Advanced Digital Antenna Module (ADAM) for receiving and exciting electromagnetic signals. The ADAM ASIC integrates a complete receiver/exciter function on a monolithic SiGe device, enabling direct digital-to-RF (Radio Frequency) and RF-to-digital transformations. The invention includes an improved analog-to-digital converter (ADC) ( ) with a novel active offset method for comparators. The novel ADC architecture ( ) includes a first circuit ( ) for receiving an input signal; a second circuit ( ) for setting a predetermined number of thresholds using a predetermined number of preamplifiers ( ) with weighted unit current sources ( ) in each of the preamplifier outputs; and a third circuit ( ) for comparing the input to the thresholds. In the preferred embodiment, the ADC ( ) includes trimmable current sources ( ). The ADC ( ) of the present invention also includes an improved comparator circuit ( ).