Steven Sm Chan

US Patent:

6525650, Feb 25, 2003

Filed:

Jun 11, 1999

Appl. No.:

09/330335

Inventors:

Steven S. Chan - Alhambra CA
George M. Hayashibara - Los Angeles CA
Davie C. Liu - Rancho Palos Verdes CA

Assignee:

TRW Inc. - Redondo Beach CA

International Classification:

H04Q 522

US Classification:

340 1469, 340 141, 340 142, 340 22, 340 221, 340 227, 455103, 4552771, 455562

Abstract:

A high density electronic switching matrix (ESM) includes several splitting modules ( ) arranged along a first axis, each including a signal input ( ) and several splitter outputs ( ). The ESM ( ) further includes several switching modules ( ) arranged along a second axis perpendicular to the first axis. Each switching module ( ) includes switching inputs ( ) coupled individually to an output of each of the splitting modules ( ). The ESM ( ) is further characterized by couplings between the splitter modules and the switching modules. The couplings are formed by mating male and female connectors ( ) integrated into the splitting modules and the switching modules. The couplings support extremely high frequency operation. The splitting modules ( ) and the switching modules ( ) may thus be coupled closely together to form a dense, high frequency, switching matrix, and may be stacked upon one another.

US Patent:

6897739, May 24, 2005

Filed:

Mar 13, 2003

Appl. No.:

10/387717

Inventors:

Steven S. Chan - Alhambra CA, US
Paul S. Lee - La Palma CA, US

Assignee:

Northrop Grumman Corporation - Los Angeles CA

International Classification:

H01P005/12

US Classification:

333127, 333113, 333137

Abstract:

A compact inline waveguide power divider is provided that comprises a primary waveguide in communication with two parallel waveguides. The two parallel waveguides are stacked on top of one another and each parallel waveguide further comprises an output port. Accordingly, an input signal is transmitted through the primary waveguide and split between the two parallel waveguides. A resistive slot is formed in each of the parallel waveguides, thereby increasing output port isolation through dissipation of reflected power from one output port to the other. Further, a stepped or tapered impedance transformation is applied in each parallel waveguide to provide wide band frequency matching. Alternately, the primary waveguide and the parallel waveguides may be configured as a waveguide power combiner rather than a divider, wherein the parallel waveguides comprise input ports and the primary waveguide comprises an output port.

US Patent:

7053847, May 30, 2006

Filed:

Aug 11, 2004

Appl. No.:

10/917986

Inventors:

Steven S. Chan - Alhambra CA, US
Te Kao Wu - Rancho Palos Verdes CA, US
Arun Bhattacharyya - El Segundo CA, US
Juan Rivera - Torrance CA, US
Phillip L. Metzen - Hermosa Beach CA, US

Assignee:

Northrop Grumman Corporation - Los Angeles CA

International Classification:

H01Q 13/12
H01Q 13/10

US Classification:

343769, 343770

Abstract:

A phased array antenna structure capable of operation at millimeter-wave frequencies and having multiple ring slot radiator elements (). The RF feed structure for each radiator element includes a feed via () extending part-way through a multi-layer structure () on which the radiator elements () are formed and a strip line feed probe () extending from the via () toward the radiator element. A key feature facilitating high-frequency operation is the inclusion of multiple mode suppressors () surrounding the via () and providing a smooth transition from a coaxial mode of RF transmission to a strip line mode of RF transmission. The feed probe () is tailored to provide either a narrow-band or a wideband frequency characteristic.

US Patent:

7432780, Oct 7, 2008

Filed:

Nov 23, 2005

Appl. No.:

11/287414

Inventors:

Steven S. Chan - Alhambra CA, US
Te Kao Wu - Rancho Palos Verde CA, US

Assignee:

Northrop Grumman Corporation - Los Angeles CA

International Classification:

H01P 5/12
H03H 7/48

US Classification:

333127, 333132, 333135, 333137

Abstract:

A rectangular-to-circular mode combiner/divider is provided. In one aspect of the invention, a power combiner is provided that comprises a plurality of rectangular waveguide ports arranged in an integral arrangement. Each rectangular waveguide port is operative to operate in a rectangular mode. The power combiner is also includes a circular waveguide port operative to operate in a circular mode, and a transition body that couples the plurality of rectangular waveguide ports to the circular waveguide port. The transition body has an inner transition cavity and an outer body operative to convert radio frequency (RF) signals between the rectangular mode and the circular mode, and provide a combined output signal at the circular waveguide port from RF signals received at the plurality rectangular waveguide ports.

US Patent:

7844253, Nov 30, 2010

Filed:

Oct 19, 2007

Appl. No.:

11/875803

Inventors:

Steven S. Chan - Fremont CA, US
George C. Huang - Los Altos Hills CA, US

Assignee:

Future Dial Inc. - Sunnyvale CA

International Classification:

H04M 1/66

US Classification:

455410, 455301, 4555755, 455106, 135139

Abstract:

A method and apparatus to use a shielded enclosure for exchanging secure data. One embodiment comprises an enclosure formed of electromagnetically shielding material that prevents an electromagnetic field from entering an interior of the enclosure or emitting from the interior of the enclosure, the enclosure sized to house a mobile electronic device; a receiver within an interior of the enclosure to receive data transferred wirelessly from a mobile electronic device placed within the enclosure; and a hardware interface having a first end external to the enclosure and a second end within the interior of the enclosure and coupled to the antenna, the hardware interface to transfer data wirelessly received by the receiver to a separate device exterior to the enclosure.

US Patent:

7880551, Feb 1, 2011

Filed:

Dec 29, 2006

Appl. No.:

12/159750

Inventors:

Steven Chan - Yonkers NY, US
Kenneth L. Shepard - Ossining NY, US
Zheng Xu - Staten Island NY, US

Assignee:

The Trustees of Columbia University in the City of New York - New York NY

International Classification:

G06F 1/00
H03B 5/00
H03B 5/18
H03L 5/00
H03L 7/00
H03L 7/099
H03L 7/24

US Classification:

331 55, 331 2, 331 96, 331117 D, 331179, 331183, 713500, 713503

Abstract:

Systems and methods for distributing a clock signal are disclosed. In some embodiments, systems for distributing a clock signal include a plurality of resonant oscillators, each comprising an inductor; and a differential clock grid that distributes the clock signal. The differential clock grid is coupled to the plurality of resonant oscillators and the clock signal, and the inductances of the inductors are configured such that a resonant frequency of the plurality of resonant oscillators is substantially equal to the frequency of the clock signal.

US Patent:

20020174436, Nov 21, 2002

Filed:

Dec 17, 2001

Appl. No.:

10/025849

Inventors:

George Wu - Oakland CA, US
Steven Chan - San Francisco CA, US
Ronald Tamura - Fremont CA, US
Elizabeth Shoemaker - Fostser City CA, US
Tze-Yee Szeto - Santa Cruz CA, US

International Classification:

H04N007/173

US Classification:

725/087000, 725/101000

Abstract:

A system for providing on demand responses to consumer impulses produced by a demand stimulus includes a computer processing system and content databases accessible by the computer-processing system having stored stimulus responses corresponding to a plurality of consumer demand stimuli in at least two categories of demand stimuli. A real-time inquiry response system associated with the computer processing system receives inquiries provided by a consumer and identifies the content category with which the consumer inquiry is associated. The computer processing system correlates consumer inquiries received by the real-time inquiry response system with stimulus responses stored in the content database based on the content category identified by the inquiry response system, so that the real-time consumer response system can return to the consumer, in real time, a stored stimulus response which correlates to the consumer inquiry. Categories of demand stimuli can include broadcast and non-broadcast information, and can include a variety of information categories or sub-categories such as music, advertisements, and scheduled events in respect to which a consumer may desire information or make a purchase.

US Patent:

20050020303, Jan 27, 2005

Filed:

May 12, 2004

Appl. No.:

10/844771

Inventors:

Steven Chan - Fremont CA, US

International Classification:

H04M001/00

US Classification:

455556100

Abstract:

A mobile communication device including an integrated stylus input unit to input data into the device, and an interface to wirelessly transmit data. In one embodiment, the integrated stylus is a handwriting stylus input device to input data by moving the stylus over a substantially flat surface. In one embodiment, the stylus includes a motion sensor embedded in an antenna extending from the device.