Chen Chen

US Patent:

20110052921, Mar 3, 2011

Filed:

Aug 5, 2010

Appl. No.:

12/851040

Inventors:

Weiliang GONG - Rockville MD, US
Werner LUTZE - Chevy Chase MD, US
Chen CHEN - Washington DC, US
Ian PEGG - Alexandria VA, US

International Classification:

B32B 9/00
G01N 33/00

US Classification:

428426, 436145, 428689, 428446, 428454

Abstract:

Provided in one embodiment is a method of charactering a fly ash composition, comprising determining a reactivity of the fly ash composition in a solution. The applicability of the findings to low water-to-solid ratios for the process of geopolymerization for the relationship between the amounts of fly ash reacted, and the compressive strength of a geopolymer cement is also described.

US Patent:

20190327124, Oct 24, 2019

Filed:

Jun 19, 2019

Appl. No.:

16/446589

Inventors:

- Greenbelt MD, US
David N. Claffey - Somerville MA, US
Chen Chen - Burlingame CA, US
Feng Zhang - Greenbelt MD, US
Chenshu Wu - Greenbelt MD, US
Chau-Wai Wong - Raleigh NC, US
Beibei Wang - Clarksville MD, US
Oscar Chi-Lim Au - San Jose CA, US
K. J. Ray Liu - Potomac MD, US

Assignee:

ORIGIN WIRELESS, INC. - Greenbelt MD

International Classification:

H04L 27/36
H04B 1/38
H04W 72/04

Abstract:

Method, apparatus and systems for object tracking are disclosed. In one example, a system for tracking a plurality of objects in a venue is disclosed. The system comprises a transmitter configured for transmitting a series of probe signals in a broadcasting manner through a wireless multipath channel, wherein the wireless multipath channel is impacted by a movement of at least one of the plurality of objects in the venue; and a plurality of heterogeneous target wireless receivers each of which is associated with an object of the plurality of objects in the venue. Each of the plurality of heterogeneous target wireless receivers is configured for: receiving the series of probe signals through the wireless multipath channel between the heterogeneous target wireless receiver and the transmitter, obtaining at least one time series of channel information (TSCI) of the wireless multipath channel based on the series of probe signals received by the heterogeneous target wireless receiver, and tracking the object associated with the heterogeneous target wireless receiver based on the at least one TSCI.

US Patent:

20190097865, Mar 28, 2019

Filed:

Nov 28, 2018

Appl. No.:

16/203299

Inventors:

- Greenbelt MD, US
Feng Zhang - Greenbelt MD, US
Chen Chen - Burlingame CA, US
Beibei Wang - Clarksville MD, US
Chenshu Wu - Greenbelt MD, US
Hangfang Zhang - Greenbelt MD, US
Chau-Wai Wong - Raleigh NC, US
David N. Claffey - Somerville MA, US
Chun-I Chen - Brookville MD, US
Hung-Quoc Duc Lai - Parkville MD, US
Min Wu - Clarksville MD, US
Yi Han - Ellicott City MD, US
Oscar Chi-Lim Au - San Jose CA, US
K. J. Ray Liu - Potomac MD, US

Assignee:

ORIGIN WIRELESS, INC. - Greenbelt MD

International Classification:

H04L 27/36
H04B 1/38
H04W 72/04

Abstract:

Apparatus, systems and methods for recognizing and classifying events in a venue based on a wireless signal are disclosed. In one example, a disclosed system comprises a first transmitter, a second transmitter, at least one first receiver, at least one second receiver, and an event recognition engine, in the venue. The first transmitter transmits a training wireless signal through a wireless multipath channel impacted by a known event in the venue in a training time period associated with the known event. Each first receiver receives asynchronously the training wireless signal, and obtains, asynchronously based on the training wireless signal, at least one time series of training channel information of the wireless multipath channel between the first receiver and the first transmitter. The second transmitter transmits a current wireless signal through the wireless multipath channel impacted by a current event in a current time period associated with the current event. Each second receiver receives asynchronously the current wireless signal, and obtains, asynchronously based on the current wireless signal, at least one time series of current channel information of the wireless multipath channel between the second receiver and the second transmitter. The event recognition engine trains a classifier based on the training channel information; and apples the classifier to: classify the current channel information and associate the current event with at least one of: a known event, an unknown event and another event.

US Patent:

20190020530, Jan 17, 2019

Filed:

Sep 9, 2018

Appl. No.:

16/125748

Inventors:

- Greenbelt MD, US
Masato MARUMO - Tokyo, JP
Beibei WANG - Clarksville MD, US
Hung-Quoc Duc LAI - Parkville MD, US
K. J. Ray LIU - Potomac MD, US
Chen CHEN - Burlingame CA, US
Qinyi XU - College Park MD, US
Yi HAN - Ellicott City MD, US
Feng ZHANG - Greenbelt MD, US
Zoltan SAFAR - Ellicott City MD, US

Assignee:

ORIGIN WIRELESS, INC. - Greenbelt MD

International Classification:

H04L 27/36
H04W 72/04
H04B 1/38

Abstract:

The present teaching relates to wireless Internet of Things. In one example, a time reversal client is disclosed. The time reversal client comprises a processor, a memory communicatively coupled with the processor, and a set of instructions, when executed by the processor based on the memory, that cause the time reversal client to perform the following steps: communicatively coupling with a time reversal server through a network, obtaining a set of channel state information (CSI), wherein the set of CSI is captured when at least one probing signal is sent from the wireless transmitter to the wireless receiver through a wireless multipath channel associated with a space, and causing the set of CSI to be sent to the time reversal server through the network.

US Patent:

20180365975, Dec 20, 2018

Filed:

Dec 9, 2016

Appl. No.:

16/060710

Inventors:

- Greenbelt MD, US
Feng Zhang - Greenbelt MD, US
Chen Chen - College Park MD, US
Beibei Wang - Clarksville MD, US
Zoltan Safar - Ellicott City MD, US
Yi Han - Ellicott City MD, US
Hung-Quoc Duc Lai - Parkville MD, US
K. J. Ray Liu - Potomac MD, US

International Classification:

G08B 29/18
G08B 13/181
H04B 7/06
G01S 13/00
G01S 13/56

Abstract:

An apparatus for detecting events includes a processor and a storage device storing instructions that when executed by the processor cause the processor to train a classifier for classifying channel state information (CSI) and detecting an event based on the classification of the CSI obtained during a monitoring phase. The training of the classifier includes: for each of the known events to be detected, during a time period in which the known event occurs in a venue, obtain training CSI of a wireless multipath channel between a wireless transmitter and a wireless receiver in the venue, in which the training CSI is derived from one or more probing signals sent from the transmitter through the wireless multipath channel to the receiver, and train the classifier based on the known events and the training CSI associated with each of the events.