Jianfeng Wang

US Patent:

8467357, Jun 18, 2013

Filed:

Dec 5, 2008

Appl. No.:

12/746279

Inventors:

Jianfeng Wang - Ossining NY, US
Dave A. T. Cavalcanti - Ossining NY, US
Kiran S. Challapali - New City NY, US

Assignee:

Koninklijke Philips Electronics N.V. - Eindhoven

International Classification:

H04W 4/00

US Classification:

370338

Abstract:

A flexible wireless system and method that support both centralized and distributed modes of MAC protocols, use a new recurring MAC superframe comprising: a beacon period, a data/sense/sleep period for data selective communication, sleep and channel sensing for detecting primary users in cognitive systems; and a signaling window used for exchanging network entry messages and channel reservation requests, the system including beacon operation, a peer beacon device in distributed mode and a master beacon device in centralized mode which are used to selectively participate in the beacon operation, as well as a slave beacon device associated with the master device. The system may employ controlled channel access for the beacon period, the channel access being reservation based. The invention provides a unified MAC protocol that can be adopted in the standards, and supports flexible operation in distributed mode or centralized mode, and seamless transfer from one to the other.

US Patent:

8576747, Nov 5, 2013

Filed:

Nov 24, 2008

Appl. No.:

12/744422

Inventors:

Jianfeng Wang - Ossining NY, US
Kiran S. Challapali - New City NY, US
Dave A. T. Cavalcanti - Ossining NY, US

Assignee:

Koninklike Philips N.V. - Eindhoven

International Classification:

H04L 12/28

US Classification:

370254

Abstract:

In a distributed-control cognitive radio network, each secondary user () in a network broadcasts parameters () that indicate the minimum quiet-period sensing demand for regular quiet-periods that the device requires for reliable detection of a primary user (). Each device () in the network adjusts its quiet-period sensing rate to accommodate the highest minimum sensing demand (), thereby providing optimal efficiency relative to quiet-period support while assuring that all devices () in the network are provided at least their minimum quiet-period sensing demand (). Both the interval between regular quiet-periods and the duration of these quiet-periods are negotiated among the devices on the network (). A quiet-period index () is used to synchronize all of the devices to a common time base. Techniques are also provided for efficient coordination of on-demand quiet-period requests, and for supporting different quiet-period schedules for multiple classes of primary users.

US Patent:

20060209772, Sep 21, 2006

Filed:

Mar 15, 2005

Appl. No.:

11/080041

Inventors:

Yuguang Fang - Gainesville FL, US
Jianfeng Wang - Gainesville FL, US
Dapeng Wu - Gainesville FL, US

Assignee:

UNIVERSITY OF FLORIDA RESEARCH FOUNDATION, INC. - GAINESVILLE FL

International Classification:

H04Q 7/24

US Classification:

370338000, 370445000

Abstract:

A method of simultaneously transmitting and receiving multiple data packets over wireless channels among the nodes of a wireless network is provided. The method includes automatically selecting a master sending node and corresponding master receiving node in response to an omni-directionally transmitted request to send during a contention period. The method also includes selecting a slave sending node and corresponding slave receiving node if a spatial reuse ratio correspond to the master-node pair is less than a predetermined threshold and if directional data transmissions between the slave sending node and corresponding slave receiving node avoid interfering with directional data transmissions between the master nodes and other pairs of slave nodes. The method further includes causing the master sending node and slave sending node to directionally transmit data packets during a coordination period.

US Patent:

20060268760, Nov 30, 2006

Filed:

May 17, 2005

Appl. No.:

11/131103

Inventors:

Yuguang Fang - Gainesville FL, US
Jianfeng Wang - Gainesville FL, US
Dapeng Wu - Gainesville FL, US

Assignee:

UNIVERSITY OF FLORIDA RESEARCH FOUNDATION, INC. - GAINESVILLE FL

International Classification:

H04Q 7/00

US Classification:

370328000

Abstract:

A method for conveying digitally encoded data within a Wireless Local Area Network (WLAN) using a contention based Media Access Control (MAC) protocol. In the method, a multi-beam access point can transmit a channel contention request and responsively receive channel contention responses. A set of nodes can be determined based upon the channel contention responses. Each node of the determined set can be assigned one beam of the multi-beam access point. The nodes can use the assigned beams to simultaneously communicate with said multi-beam access point in a collision-free fashion along an assigned beam.

US Patent:

20100246434, Sep 30, 2010

Filed:

Nov 24, 2008

Appl. No.:

12/744409

Inventors:

JIANFENG WANG - OSSINING NY, US
KIRAN CHALLAPALI - NEW CITY NY, US

Assignee:

KONINKLIJKE PHILIPS ELECTRONICS, N.V. - EINDHOVEN

International Classification:

H04L 12/26
H04L 12/28

US Classification:

370253, 370255

Abstract:

A device () scans and classifies each channel within a spectrum of channels (-) as being occupied or unoccupied (), and, if occupied, whether it is occupied by a primary user (), a secondary user (), or an unknown user (). As a secondary device (), transmissions are avoided on channels occupied by primary users (). The device selectively joins an existing network of secondary devices, or establishes a new network on an unoccupied channel (), based on the quality of service (QoS) that the channel can provide and/or other factors. If the device is paired with a target device (), the paired device advertises itself on a selected channel (-) for a period that is at least as long as the time required to scan all channels, to facilitate discovery in the event that the target device is also in a search mode. The advertising duration randomly alternates () among integer multiples of the scan duration.

US Patent:

20100271948, Oct 28, 2010

Filed:

Dec 5, 2008

Appl. No.:

12/746261

Inventors:

Kiran S. Challapali - New City NY, US
Jianfeng Wang - Ossining NY, US

Assignee:

KONINKLIJKE PHILIPS ELECTRONICS, N.V. - EINDHOVEN

International Classification:

H04L 12/26

US Classification:

370235

Abstract:

A source-assisted channel management method in a distributed spectrum cognitive radio wireless network handling a source of multimedia stream data handles a plurality of communicating devices () forming a group, and manages channels with no separate controller that is referenced in applicable IEEE standard. The source makes the reservation on behalf of the device group knows traffic schedule, and determines out-of-band channel scanning, back up channel and channel vacation. The method uses a flexible MAC superframe structure and proactively scans for back-up channels which could be used in lieu of the current channel, identifies devices in the group which should vacate a current channel when any one device from the group of communicating devices () detects an incumbent, and make a determination as to when the wireless network should vacate the current channel based on said traffic schedule. The method ensures that no interference is caused to existing users and maintains QoS.

US Patent:

20100284340, Nov 11, 2010

Filed:

Jan 23, 2009

Appl. No.:

12/812640

Inventors:

Vasanth Gaddam - Tarrytown NY, US
Monisha Ghosh - Chappaqua NY, US
Jianfeng Wang - Ossining NY, US

Assignee:

KONINKLIJKE PHILIPS ELECTRONICS, N.V. - EINDHOVEN

International Classification:

H04W 40/00

US Classification:

370328

Abstract:

A first wireless device communicates data to a second wireless device. The first wireless device employs at least one of a first interleaving scheme and a first sub-carrier mapping scheme to produce a first data packet from a first plurality of data bits, and transmits the first data packet to the second wireless device. When the first data packet is not received correctly by the second wireless device, then the first wireless device employs at least one of a second interleaving scheme and a second sub-carrier mapping scheme to create a second data packet from the first plurality of data bits, and transmits the second data packet to the second wireless device.

US Patent:

20100304772, Dec 2, 2010

Filed:

Dec 5, 2008

Appl. No.:

12/746271

Inventors:

Jianfeng Wang - Ossining NY, US
Kiran S. Challapali - New City NY, US

Assignee:

KONINKLIJKE PHILIPS ELECTRONICS, N.V. - EINDHOVEN

International Classification:

H04W 74/00

US Classification:

455509

Abstract:

To facilitate multi-channel communications over distributed-control radio networks, the timing of networks on multiple substantially independent channels are adjusted () so as to establish a common time base among the networks. With this common time base, data is transmitted concurrently (), using the bandwidth provided by the multiple networks. To further optimize the efficiency of this technique for cognitive radio networks, the quiet period (QP) and signaling window (SW) on each network are scheduled () to provide overlapping quiet periods (QP) and/or overlapping signaling windows (SW). Preferably, each multi-channel user is assigned (360) the same time slot in the beacon periods () of the network on each channel, thereby facilitating efficient beacon transmission and reception.