Chenxi X Zhu from 11452 Mallard Creek Trl, Fairfax, VA 22033, age 55, Phone: (703)9348389

Name / Title

Company / Classification

Phones & Addresses

Chenxi Zhu
Principal

Mallard Creek Networks LLC
Business Services at Non-Commercial Site · Nonclassifiable Establishments

11452 Mallard Crk Trl, Fairfax, VA 22033

Resumes

Chenxi Zhu

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Us Patents

Scheme For Operating A Wireless Station Having Directional Antennas
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US Patent:

7630343, Dec 8, 2009
Filed:

Mar 27, 2006
Appl. No.:

11/389014
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Tamer Nadeem - Plainsboro NJ, US
Jonathan Agre - Brinklow MD, US
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04Q 7/00
US Classification:

370334, 370328, 370342, 4555621, 342368
Abstract:

Disclosed is a wireless station having a receiver and a network allocation vector associated with each of a plurality of directional antennas. The receivers concurrently listen for frames from remote stations. When any receiver detects a frame from a remote station, the receiver activates its associated NAV. The station has one or more transmitters that can transmit using the antennas. While transmitting a signal using an antenna, the receivers associated with any non-transmitting antennas continue to listen for signals from remote stations. The station cancels any signals from the transmitting antenna received by the non-transmitting antennas. To perform the cancellation, the station performs a self-calibration procedure. The station can self-calibrate by either silencing neighboring stations or by inserting null tones into a transmitted calibration signal.

Interference Measuring And Mapping Method And Apparatus For Wireless Networks Using Relay Stations
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US Patent:

7643429, Jan 5, 2010
Filed:

Jul 13, 2007
Appl. No.:

11/777566
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Dorin Viorel - Calgary, CA
Jagan Seshadri - Calgary, CA
Jonathan Agre - Brinklow MD, US
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04J 1/16
US Classification:

370241, 370252, 370203, 370208, 455 6711, 455 631, 455 6713, 4555621, 375148, 375147, 375267
Abstract:

Interference levels occurring at one or more stations in a wireless network, where each of said one or more stations is a base station or a relay station. The measured interference levels are mapped by building a first matrix including noise plus interference occurring at each of the one or more stations, respectively, and scheduled transmissions at predetermined times by each relay station respectively are mapped by building a second matrix. The first matrix and the second matrix are multiplied in order to determine the noise plus interference impact upon each base station by each relay station so that a network schedule can be generated in order to increase bandwidth efficiency in the network.

System And Method For Assigning Channels In A Wireless Network
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US Patent:

7756198, Jul 13, 2010
Filed:

Oct 16, 2006
Appl. No.:

11/549892
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Takeo Hamada - Cupertino CA, US
Jonathan R. Agre - Brinklow MD, US
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04Q 1/20
US Classification:

375225
Abstract:

A method for assigning channels in a wireless network includes receiving from each of a plurality of a first type of wireless components a total average data rate. Each total average data rate is based on an average data rate for each of a first plurality of a second type of wireless components coupled to the respective first type of wireless component. The method also includes determining at least one channel parameter for a first wireless component of the plurality of the first type of wireless components based on a ratio of the total average data rate associated with the respective first wireless component to the total average data rate associated with the plurality of the first type of wireless components. The method further includes allocating a channel to the first wireless component based on the determined at least one channel parameter.

Proportional Fair Scheduler For Ofdma Wireless Systems With Qos Constraints
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US Patent:

7768973, Aug 3, 2010
Filed:

Apr 20, 2007
Appl. No.:

11/785892
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Tolga Girici - Hyattsville MD, US
Jonathan Russell Agre - Brinklow MD, US
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04W 4/00
US Classification:

370329, 370343, 370344, 455450
Abstract:

Available bandwidth and power for users demanding real time and non-real time data traffic are scheduled, while maximizing proportional fairness for the users over a plurality of time slots, and meeting quality of service constraints for real time data traffic users. The Lagrangian multipliers are used to define a function which includes the proportional fair capacity over the plurality of time slots, and the total power, the total bandwidth, and rate of the real time users' constraints. A maximum of the function is determined for each time slot by binary searching two parameters while observing the total power and total bandwidth. An optimal allocation of the bandwidth and power for the time slot is calculated using the two parameters.

Reuse Pattern Network Scheduling Using Interference Levels
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US Patent:

7877097, Jan 25, 2011
Filed:

Jul 13, 2007
Appl. No.:

11/777385
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Dorin Viorel - Calgary, CA
Jagan Seshadri - Calgary, CA
Jonathan Agre - Brinklow MD, US
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04W 40/00
US Classification:

455446, 370329, 370331, 445450, 4455531
Abstract:

Interference levels occurring at one or more stations are mapped, and a reuse pattern is generated, based on the mapped interference levels, including one or more reuse sets of stations capable of sharing a transmission resource. The stations within each reuse set are listed in increasing order based on their respective interference levels, and an additional station is added to a reuse set, as long as the cumulative interference level within the reuse set is below a threshold interference level and the additional station is not already listed in another reuse set. A network schedule is updated based on the reuse pattern to increase bandwidth efficiency in the network.

Device And Method For Reducing Overhead In A Wireless Network
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US Patent:

7899056, Mar 1, 2011
Filed:

Jan 13, 2009
Appl. No.:

12/352887
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Masato Okuda - Tokorozawa, JP
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04L 12/28
US Classification:

370393, 370473, 370477
Abstract:

A method for reducing overhead includes identifying a plurality of packets that are all to comprise at least one common piece of security information. The method also includes concatenating the plurality of packets into a single jumbo packet. The method further includes applying a single set of security information to the jumbo packet. The single set of security information is based on the at least one common piece of security information.

System And Method For Reusing Wireless Resources In A Wireless Network
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US Patent:

7917149, Mar 29, 2011
Filed:

Nov 7, 2006
Appl. No.:

11/557428
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Ching-Fong Su - Milpitas CA, US
Jonathan R. Agre - Brinklow MD, US
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04W 72/00
US Classification:

455450, 455451, 4554521, 455509, 455512, 455 7, 455 9, 455 111, 455 131, 455 631, 455 6713, 455443
Abstract:

A method for reusing wireless resources in a wireless network, includes determining the probability of a first communication with a first relay station experiencing interference from a second relay station. The method also includes, upon determining that the probability of experiencing interference from the second relay station is greater than an interference threshold: allocating a first wireless resource to the first relay station and the second relay station; designating the first wireless resource as a primary wireless resource for the first relay station; designating the first wireless resource as a secondary wireless resource for the second relay station; allocating a second wireless resource to the second relay station; and designating the second wireless resource as a primary wireless resource for the second relay station.

Proportional Fair Scheduler For Ofdma Wireless Systems
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US Patent:

7924698, Apr 12, 2011
Filed:

Apr 20, 2007
Appl. No.:

11/785893
Inventors:

Chenxi Zhu - Gaithersburg MD, US
Jonathan Russell Agre - Brinklow MD, US
Assignee:

Fujitsu Limited - Kawasaki
International Classification:

H04B 7/212
US Classification:

370208, 370329, 370431
Abstract:

A scheduler and a method schedule available power and bandwidth to users. Equations for a continuous bandwidth allocation of a total bandwidth, and/or a continuous power distribution of a total power, are set up using Lagrangian multipliers to include constraints in a function that is maximum when a fair capacity is maximum. The continuous bandwidth allocation and/or the continuous power distribution represent sets of values corresponding to users that maximize the function. The equations are solved using waterfilling methods, wherein the continuous power distribution is determined for a previously determined bandwidth allocation, and/or the continuous bandwidth allocation is calculated for a previously determined power distribution.