Chiu Yeung Ngo

US Patent:

6339585, Jan 15, 2002

Filed:

May 5, 1998

Appl. No.:

09/073095

Inventors:

Samir N. Hulyalkar - Bensalem PA
Chiu Y. Ngo - Ossining NY
Dinesh C. Verma - Millwood NY

Assignee:

Philips Electronics North America Corp. - New York NY

International Classification:

G01R 3108

US Classification:

370226, 370315, 370350

Abstract:

A method of transmitting information in a communications system. The method preferably includes the steps of establishing a communications link between a base station and a temporary node, attempting to maintain a second communication link between the base station and a wireless terminal and upon a determination that the second link cannot be established or satisfactorily maintained, transmitting information from the first base station to the temporary node so that the temporary node can retransmit the information to the wireless terminal, attempting to reestablish the second link and upon such establishment, discontinuing the transmission of subsequent information from the base station to the temporary node and directly transmitting the subsequent information to the wireless terminal from the base station. A system to carry out the foregoing steps is also provided.

US Patent:

6377549, Apr 23, 2002

Filed:

Jun 30, 1998

Appl. No.:

09/107526

Inventors:

Chiu Y. Ngo - Ossining NY
Andreas Hettich - Aachen, DE

Assignee:

U.S. Philips Corporation - New York NY

International Classification:

H04L 1226

US Classification:

370233, 370328, 37039521

Abstract:

A system which determines whether to accept a wireless connection to a network device receives a request to initiate the wireless connection to the network device, and then determines, in response to the request, a nominal cell rate at which cells are exiting from a buffer in the network device for the requested wireless connection. Thereafter, the system determines an amount of buffer space in the network device required to accommodate the connection, and decides whether to accept the wireless connection based on the nominal cell rate and the amount of buffer space required to accommodate the connection.

US Patent:

6510150, Jan 21, 2003

Filed:

Dec 21, 1998

Appl. No.:

09/217470

Inventors:

Chiu Y. Ngo - Ossining NY

Assignee:

Koninklijke Philips Electronics N.V. - Eindhoven

International Classification:

H04J 306

US Classification:

370347, 370350, 3703951, 370503

Abstract:

A method for synchronizing timestamps in a network (e. g. , a wireless ATM network) that includes a control node and a plurality of other nodes that communicate with one another over a common channel mediated by a medium-access control subsystem (e. g. , one that uses a reservation-based TDMA protocol). At the control node, when a timestamp command is sent from MAC to PHY over the MAC-PHY interface, the current timestamp value at the control node is captured from the MAC-PHY interface. The captured timestamp value is then added by a timestamp update interval, T, and stored to become the timestamp value included in the next timestamp transmission exactly T seconds later. At each other node, when the timestamp command is received by PHY and sent to MAC over the MAC-PHY interface, the current timestamp value at the respective other node is captured from the MAC-PHY interface. The captured timestamp value is then compared with the timestamp value contained in the timestamp command and the difference, if any, is stored in an offset_register. This offset value will later be added to the timestamp counter in a non-time-critical manner under software control before the arrival of the next timestamp command.

US Patent:

6584100, Jun 24, 2003

Filed:

Nov 17, 1998

Appl. No.:

09/193435

Inventors:

Chiu Y. Ngo - Ossining NY

Assignee:

Koninklijke Philips Electronics N.V. - Eindhoven

International Classification:

H04J 317

US Classification:

370377, 370336, 370338, 370345, 370346, 370458

Abstract:

The system establishes a transmission sequence for effecting communications between plural terminals in a wireless network. This transmission sequence is defined by a control data frame comprised of plural slots, each of which can be allocated for communication between one pair of the plural terminals. In operation, the system begins by generating a transmit/receive matrix for the plural terminals in the wireless network. This transmit/receive matrix includes plural rows and plural columns, where each of the plural rows corresponds to a terminal and each of the plural columns corresponding to a same or different terminal. At each row/column nexus, the transmit/receive matrix includes an entry which indicates whether communications are to be effected between a pair of terminals that corresponds thereto. Slots in the control data frame are then allocated to pairs of the plural terminals based on these entries in the transmit/receive matrix.

US Patent:

6751196, Jun 15, 2004

Filed:

Aug 27, 1997

Appl. No.:

08/919052

Inventors:

Samir N. Hulyalkar - Ossining NY
Yonggang Du - Aachen, DE
Christoph Herrmann - Aachen, DE
Chiu Ngo - Ossining NY
Peter Klaus May - Aachen, DE

Assignee:

Philips Electronics North America Corp. - New York NY

International Classification:

H04L 1226

US Classification:

370252, 370255

Abstract:

Centrally controlled wireless networks require reliable communications between the central controller and each of the stations within the wireless networks. The structure of a wireless network is often dynamic, or ad-hoc, as stations enter and exit the network, or are physically relocated. The selection of the central controller for the network may also be dynamic, either because the current central controller desires to exit the network, or because the communication between the current central controller and one or more of the stations is poor. This invention discloses a method and apparatus for assessing the quality of the communication paths among all stations in the network. This assessment is useful as a continual monitor of the quality of the network, and can be utilized to select an alternative central control station based upon the quality of communication paths to and from this station. Additionally, the quality assessment can be utilized to establish relay communication paths, as required.

US Patent:

6798838, Sep 28, 2004

Filed:

Mar 2, 2000

Appl. No.:

09/517726

Inventors:

Chiu Yeung Ngo - Ossining NY

Assignee:

Koninklijke Philips Electronics N.V. - Eindhoven

International Classification:

H04N 712

US Classification:

37524019, 375240, 725 95, 725 96

Abstract:

There is disclosed a wireless communication device capable of receiving an incoming RF data signal and generating therefrom a base layer data stream and at least one enhancement layer data stream. The wireless communication device comprises: 1) a base layer decoder, 2) at least one enhancement layer decoder, 3) a variable mode receiver for demodulating the RF incoming RF data signals in a plurality of physical modes, such as BPSK, QPSK, QAM, and the like, and at a plurality of code rates and 4) a receiver mode controller for controlling the physical modes of the variable mode receiver. The receiver mode controller causes a first demodulated output signal of the variable mode receiver to be transferred to the base layer decoder when the variable mode receiver is operating in a first physical mode and causes a second demodulated output signal of the variable mode receiver to be transferred to the at least one enhancement layer decoder when the variable mode receiver is operating in a second physical mode. There also is disclosed a second wireless communication device for transmitting an outgoing RF data signal comprising a base layer data stream and at least one enhancement layer data stream. The second wireless communication device comprises: 1) a base layer encoder, 2) at least one enhancement layer encoder, 3) a variable mode transmitter for modulating an input signal in a plurality of physical modes and at a plurality of code rates to produce the outgoing RF data signal; and 4) a transmitter mode controller for controlling the plurality of physical modes of the variable mode transmitter.

US Patent:

7110366, Sep 19, 2006

Filed:

Feb 20, 2002

Appl. No.:

10/080184

Inventors:

Samir N. Hulyalkar - Ossining NY, US
Yonggang Du - Aachen, DE
Christoph Herrmann - Aachen, DE
Chiu Ngo - Ossining NY, US
Peter Klaus May - Aachen, DE

Assignee:

Koninklijke Philips Electronics N.V. - Eindhoven

International Classification:

H04L 12/26
H04B 7/216

US Classification:

370252, 370254, 370338

Abstract:

Centrally controlled wireless networks require reliable communications between the central controller and each of the stations within the wireless networks. The structure of a wireless network is often dynamic, or ad-hoc, as stations enter and exit the network, or are physically relocated. The selection of the central controller for the network may also be dynamic, either because the current central controller desires to exit the network, or because the communication between the current central controller and one or more of the stations is poor. This invention discloses a method and apparatus for assessing the quality of the communication paths among all stations in the network. This assessment is useful as a continual monitor of the quality of the network, and can be utilized to select an alternative central control station based upon the quality of communication paths to and from this station. Additionally, the quality assessment can be utilized to establish relay communication paths, as required.

US Patent:

7397862, Jul 8, 2008

Filed:

Oct 18, 2005

Appl. No.:

11/253855

Inventors:

Xuemei Ouyang - San Jose CA, US
Chiu Ngo - San Francisco CA, US

Assignee:

Samsung Electronics Co., Ltd. - Suwon

International Classification:

H04L 1/02

US Classification:

375267, 370208, 370310, 375316, 375299, 375347, 375260, 375286

Abstract:

An improved interleaver design to fully explore the diversity of the MIMO OFDM systems provides higher diversity gain than usual. A method for wireless data communication using such interleaver design implements parsing a bit stream into multiple spatial data streams, interleaving the bits in each spatial data stream by performing bit circulation to increase diversity of the wireless system, and transmitting the bits of each spatial data stream.