Thomas D Chen

US Patent:

8601587, Dec 3, 2013

Filed:

Sep 3, 2010

Appl. No.:

12/875854

Inventors:

William S. Powell - Gibsonton FL, US
Thomas L. Chen - Seminole FL, US

Assignee:

Raytheon Company - Waltham MA

International Classification:

G06F 11/00
G06F 12/14
G06F 12/16
G08B 23/00

US Classification:

726 25

Abstract:

According to certain embodiments, a cyber threat analysis system generates a network model of a network infrastructure that is used by an organization, assigns a weighting value to each of a plurality of network elements of the network infrastructure according to a relative importance of the each network element to the organization, and generates an attack vector according to a determined vulnerability of the network infrastructure. The attack vector represents one or more illicit actions that may be performed to compromise the network infrastructure. The system may simulate, using a network modeling tool, the attack vector on the network model to determine one or more resulting ramifications of one or more of the plurality of network elements due to the attack vector, and determine a criticality level of the attack vector according to the weighting value of the one or more network elements.

US Patent:

20190363702, Nov 28, 2019

Filed:

May 24, 2018

Appl. No.:

15/989156

Inventors:

- Cupertino CA, US
Taiyun CHI - Atlanta GA, US
Thomas CHEN - Atlanta GA, US

International Classification:

H03K 5/00
H04B 1/00
H03F 3/195
H03G 3/30

Abstract:

An RF frontend IC device includes an RF transceiver to transmit and receive RF signals and a frequency synthesizer to perform frequency synthetization to operate within a predetermined frequency band. The frequency synthesizer generates an LO signal to the RF transceiver to enable the RF transceiver to transmit and receive RF signals within the predetermined frequency band. The frequency synthesizer includes a QPG circuit to generate signals shifted in phases based on the LO signal and a phase shifting circuit to generate quadrant signals based on the signals shifted in phases. Each of the quadrant signals corresponds to one of the four quadrants in phases in the respective quadrant spaces. The phase shifting circuit includes multiple phase switches operable in a collaboration manner to further shift in phase based on the signal shifted in phases to generate the quadrant signals in proper quadrant spaces.

US Patent:

20190356348, Nov 21, 2019

Filed:

May 15, 2018

Appl. No.:

15/980391

Inventors:

- Cupertino CA, US
Taiyun CHI - Atlanta GA, US
Min-Yu HUANG - Atlanta GA, US
Hua WANG - Atlanta GA, US
Thomas CHEN - Atlanta GA, US

International Classification:

H04B 1/16
H03F 3/19
H03D 7/14

Abstract:

According to one embodiment, a compact broadband radio frequency (RF) receiver circuit includes a low noise amplifier which includes a first amplifier stage, a second amplifier stage, an inter-stage network including a higher order filter network, where the inter-stage network is coupled between the first amplifier stage and the second amplifier stage, and a double resonance transformer network coupled to an output of the second amplifier stage. The RF receiver circuit includes a low pass filter and a mixer circuit coupled between the low noise amplifier and the low pass filter.

US Patent:

20190356362, Nov 21, 2019

Filed:

May 15, 2018

Appl. No.:

15/980529

Inventors:

- Cupertino CA, US
Hua WANG - Atlanta GA, US
Thomas CHEN - Atlanta GA, US

International Classification:

H04B 7/0404
H04B 1/00

Abstract:

According to one embodiment, a compact broadband radio frequency (RF) frontend circuit includes a number of single-channel transceivers, a number of analog to digital converters (ADCs), where each of the ADCs is coupled to one of the single-channel transceivers, a number of digital to analog converters (DACs), where each of the DACs is coupled to one of the single-channel transceivers, and a digital signal processing (DSP) unit coupled to the ADCs and the DACs. The DSP unit is configured to generate a first set of digital data streams simultaneously and each of the first set of digital data streams is converted by a respective one of the DACs into an analog data stream to be transmitted to a remote device by a respective one of the single-channel transceiver.

US Patent:

20190348379, Nov 14, 2019

Filed:

May 8, 2018

Appl. No.:

15/974542

Inventors:

- Cupertino CA, US
Taiyun Chi - Atlanta GA, US
Thomas Chen - Atlanta GA, US

International Classification:

H01L 23/66
H01L 23/00

Abstract:

A flip chip IC device utilized in RF transceivers includes a bare die having a number of metalized pads and each metalized pad has a solder ball deposited thereon. The flip chip IC device further includes a substrate having a number of connector pads corresponding to the metalized pads. The connector pads are connected to one or more electronic components disposed on the substrate via a number of connector strips. The bare die is flipped up-side-down such that the metalized solder pads are aligned and connected with the connector pads of the substrate via the solder balls. At least one of the connector strips includes a strip section having an uneven strip width configured to compensate an impedance of a transmission line formed based on a connection between a metalized pad of the bare die and a connector pad of the substrate to match predetermined impedance.

US Patent:

20190334560, Oct 31, 2019

Filed:

Apr 27, 2018

Appl. No.:

15/965694

Inventors:

- Cupertino CA, US
Hua Wang - Atlanta GA, US
Thomas Chen - Atlanta GA, US

International Classification:

H04B 1/00
H03F 3/19
H03F 3/24
H03F 1/56

Abstract:

According to one embodiment, a transmit/receive (T/R) switch includes a transmit switch, between a transmit port and an antenna port, a receive switch, between a receive port and the antenna port, a transmit inductor, coupled in parallel between the transmit switch the transmit port, and a receive inductor, coupled in parallel between the transmit switch the transmit port. The T/R switch can be co-designed with a power amplifier (PA) output matching circuit.

US Patent:

20190245507, Aug 8, 2019

Filed:

Feb 7, 2018

Appl. No.:

15/891328

Inventors:

- Cupertino CA, US
Hua Wang - Atlanta GA, US
Thomas Chen - Atlanta GA, US

International Classification:

H03H 7/38
H03H 7/01

Abstract:

According to one embodiment, a matching network circuit includes a first capacitor coupled, in parallel, to an input port of the matching network circuit; a broadband on-chip transformer coupled, in parallel, to the first capacitor, where the broadband on-chip transformer includes a primary winding and a secondary winding, where the secondary winding is a partial winding. The matching network circuit includes a second capacitor coupled, in series, in between the broadband on-chip transformer and an output port of the matching network circuit.

US Patent:

20190221934, Jul 18, 2019

Filed:

Jan 18, 2018

Appl. No.:

15/874850

Inventors:

- San Jose CA, US
Thomas Chen - Atlanta GA, US
Taiyun Chi - Atlanta GA, US

International Classification:

H01Q 5/30
H04B 1/00

Abstract:

According to one embodiment, an antenna includes multiple high-band (HB) radiation elements and a low-band (LB) radiation element. Each HB radiation element is configured to resonate or excite within a first frequency band to transmit and/or receive RF signals associated with the first frequency band. The LB band radiation element is configured to resonate or excite within a second frequency band to transmit and/or receive RF signals associated with the second frequency band. The HB radiation elements are arranged such that the distance between any two of the HB radiation elements is at least a half of a wavelength associated with the first frequency band. The LB radiation element is surrounded by the HB radiation element, for example, in a symmetrical manner.