Gang Xueying Liu

US Patent:

6486643, Nov 26, 2002

Filed:

Aug 27, 2001

Appl. No.:

09/813078

Inventors:

Gang Liu - Novi MI

Assignee:

Analog Technologies, Inc. - Farmington Hills MI

International Classification:

G05F 159

US Classification:

323268, 323274, 323284

Abstract:

An H bridge regulating system for driving an electric load includes a linear output stage and switch mode output stage connected to opposite ends of the load. The linear output stage has a linear mode amplifier and a feedback circuit, and its amplifier generates a first output signal tied to one end of the load. This output voltage is passed through a conditioning resistor to an inverting input of the linear mode amplifier. The switch mode output stage has a switch mode amplifier and a feedback circuit, and its amplifier generates a second output signal tied to the other end of the load. Its voltage signal is passed through a second conditioning resistor to an inverting input of the switch mode amplifier. Other feedback circuit elements are also provided to create three distinct regions of operations for each of the amplifiers. Due to this novel arrangement for an H bridge circuit, and this novel method of operation involving three distinct regions of operation for the linear mode and switch mode output stages, very high power-saving energy efficiencies are achieved.

US Patent:

6636124, Oct 21, 2003

Filed:

Nov 30, 2001

Appl. No.:

10/000775

Inventors:

Gang Liu - Novi MI

Assignee:

Analog Technologies, Inc. - Sunnyvale CA

International Classification:

H03K 708

US Classification:

332109, 327172

Abstract:

A pulse width modulation (PWM) circuit has a PWM output signal that features accurate timing even in the face of interference imposed upon the control signal representative of the desired PWM duty cycle. The PWM circuit includes or has a first or switching section and a second or analog section. The second section has an operational amplifier with a summing circuit that sums two input signals, namely a triangular wave signal and the control input signal, and then amplifies the summed signal to produce a trapezoidal waveform output delivered to the second section. The first section features a two-input comparator that produces a PWM signal output with a fast transition in response to trapezoidal output fed as an input and compared to a stable reference signal. Due to the speed of the op amp, timing errors on the PWM output signal due to interference on the control signal are minimized.

US Patent:

6762997, Jul 13, 2004

Filed:

Mar 29, 2000

Appl. No.:

09/537791

Inventors:

Gang Liu - North Plainfield NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04L 1256

US Classification:

370238, 370400

Abstract:

A method is disclosed for determining the shortest paths between a source node and a destination node in a network wherein the paths satisfy imposed system constraints. In accordance with the method of the invention, candidate paths are evaluated by accumulating system parameter information from a source node and projecting the system parameter information ahead to the destination node. When the accumulated and projected system parameter information for the candidate path satisfies the imposed system constraints, the candidate path is saved for further evaluation. The candidate paths are sorted in the order such that those paths most-likely to have the shortest lengths and satisfy the imposed system constraint are evaluated first. In one embodiment of the invention, candidate paths that fail to satisfy the imposed system constraints are removed from further processing. Thus, only candidate paths that have at least one complete path that satisfies the imposed system constraints are evaluated further.

US Patent:

6782198, Aug 24, 2004

Filed:

Nov 10, 2000

Appl. No.:

09/710269

Inventors:

Gang Liu - North Plainfield NJ

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04B 1008

US Classification:

398 3, 398 4, 398 5

Abstract:

Recovery from link failure in a WDM ring network is implemented by forming an active ring and a protection ring through the same nodes. Failure in any wavelength channel of a link causes a node adjacent to the link to reroute any subsequent incoming signal from the source node and on the active ring to the protection ring and in an opposite direction. The oppositely directed signal is rerouted again at the other adjacent node back to the active ring to arrive at the destination node. The physical ring serving as the active ring to odd wavelength channels serves as the protection ring to even wavelength channels, and vice versa.

US Patent:

6801557, Oct 5, 2004

Filed:

Apr 6, 2001

Appl. No.:

09/827764

Inventors:

Gang Liu - Novi MI 48375

International Classification:

H01S 300

US Classification:

372 3809, 372 3802, 372 3803, 372 3804, 372 3807

Abstract:

A laser driver for laser sensing system having two lasers on a single PCB, thermo-electric temperature control, rapid activation, and pulse power and duration safety tables embedded in the microprocessor controller.

US Patent:

7058296, Jun 6, 2006

Filed:

Mar 12, 2001

Appl. No.:

09/805021

Inventors:

Iraj Saniee - New Providence NJ, US
Eric Bouillet - Eatontown NJ, US
Gang Liu - Denver CO, US

Assignee:

Lucent Technologies Inc. - Murray Hill NJ

International Classification:

H04J 14/00

US Classification:

398 3

Abstract:

A procedure for designing WDM optical networks provides both working circuits and protection circuits for carrying traffic demands between node pairs. The protection circuits are activated for the purpose of network recovery in case of a fault on a working circuit. Each protection circuit is link-disjoint, and preferably node-disjoint, from its corresponding working circuit. The network is subdivided into logically defined rings, such that each working and protection circuit lies on one or more of the rings. In particular embodiments of the invention, the joint routing of circuits is carried out so as to minimize the total length of the working and protection circuits according to a length that includes a weight for each link. The weight is selected to promote the efficient packing of optical fibers with wavelength channels.

US Patent:

7171036, Jan 30, 2007

Filed:

Mar 14, 2003

Appl. No.:

10/389475

Inventors:

Gang Liu - Framingham MA, US
Aaron Wallack - Natick MA, US
David Michael - Wayland MA, US

Assignee:

Cognex Technology and Investment Corporation - Mt. View CA

International Classification:

G06K 9/00

US Classification:

382145, 382151, 382168

Abstract:

An image of a semiconductor interconnection pad is analyzed to determine a geometric description of the zone regions of a multiple zone semiconductor interconnection pad. Edge detection machine vision tools are used to extract features in the image. The extracted features are analyzed to derive geometric descriptions of the zone regions of the pad, that are applied in semiconductor device inspection, fabrication, and assembly operations.

US Patent:

7466913, Dec 16, 2008

Filed:

Oct 7, 2005

Appl. No.:

11/245597

Inventors:

Iraj Saniee - New Providence NJ, US
Eric Bouillet - Eatontown NJ, US
Gang Liu - Denver CO, US

Assignee:

Alcatel-Lucent USA Inc. - Murray Hill NJ

International Classification:

H04J 14/00

US Classification:

398 3

Abstract:

A procedure for designing WDM optical networks provides both working circuits and protection circuits for carrying traffic demands between node pairs. The protection circuits are activated for the purpose of network recovery in case of a fault on a working circuit. Each protection circuit is link-disjoint, and preferably node-disjoint, from its corresponding working circuit. The network is subdivided into logically defined rings, such that each working and protection circuit lies on one or more of the rings. In particular embodiments of the invention, the joint routing of circuits is carried out so as to minimize the total length of the working and protection circuits according to a length that includes a weight for each link. The weight is selected to promote the efficient packing of optical fibers with wavelength channels.