Albert M Chan

US Patent:

7095812, Aug 22, 2006

Filed:

Jun 24, 2002

Appl. No.:

10/178922

Inventors:

Albert Chan - Cambridge MA, US
Inkyu Lee - Kearny NJ, US
Carl-Erik Wilhelm Sundberg - Chatham NJ, US

Assignee:

Agere Systems Inc. - Allentown PA

International Classification:

H03D 1/00
H04L 27/06

US Classification:

375341, 375262, 714786

Abstract:

A system employs space-time coding characterized at the transmitter by bit-interleaved coded modulation (BICM) combined with modulating several streams of the BICM encoded data for transmission over two or more antennas. Space-time coding techniques improve transmission efficiency in radio channels by using multiple transmit and/or receive antennas and coordination of the signaling over these antennas. Bit-interleaved coded modulation provides good diversity gain with higher-order modulation schemes that employ binary convolutional codes. A receiver demodulates the received signals and applies multi-input, multi-output (MIMO) demapping to estimate the BICM encoded bitstream. After deinterleaving of the BICM encoded bitstream, maximum a posteriori (MAP) decoding is applied to the resulting bit stream to generate soft output values. By applying well-known turbo-decoding principles to iteratively demap and decode, the overall receiver performance is significantly improved. The MIMO demapping and MAP decoding processes exchange likelihood information to improve the bit error rate performance over several iterations of demapping/decoding.

US Patent:

7292661, Nov 6, 2007

Filed:

Mar 20, 2000

Appl. No.:

09/528678

Inventors:

Albert M. Chan - Cambridge MA, US
Gregory W. Wornell - Wellesly MA, US

Assignee:

Massachusetts Institute of Technology - Cambridge MA

International Classification:

H04B 1/10

US Classification:

375346, 375229, 375230, 375231, 375232, 375233, 375234

Abstract:

A block-iterative equalizer is adapted for use in contemporary digital communication system receivers. In a preferred embodiment, data received over a communication channel is processed by a linear feed-forward filter and the resulting filtered signal is provided to a slicer which makes a first set of tentative symbol decisions. During later iterations, the same received data is processed by the linear feed-forward filter, the feed-forward filter parameters being modified at each iteration based on the received data and the tentative decisions are themselves filtered by a second, “feed-back” filter and used to improve the tentative decisions.

US Patent:

7359313, Apr 15, 2008

Filed:

Jun 24, 2002

Appl. No.:

10/178923

Inventors:

Albert Chan - Cambridge MA, US
Inkyu Lee - Kearny NJ, US
Carl-Erik Wilhelm Sundberg - Chatham NJ, US

Assignee:

Agere Systems Inc. - Allentown PA

International Classification:

H04J 11/00

US Classification:

370210

Abstract:

A system employs space-time coding characterized at the transmitter by bit-interleaved coded modulation (BICM) combined with multi-carrier Orthogonal Frequency Division Multiplexing (OFDM) modulation. Space-Time coding techniques improve transmission efficiency in radio channels by using multiple transmit and/or receive antennas and coordination of the signaling over these antennas. Bit-interleaved coded modulation provides good diversity gain with higher-order modulation schemes that employ binary convolutional codes. OFDM modulation allows for wideband transmission over frequency selective radio channels. A receiver demodulates the OFDM signal and applies multi-input, multi-output (MIMO) demapping to estimate the BICM encoded bitstream. After deinterleaving of the BICM encoded bitstream, maximum a posteriori (MAP) decoding is applied to the resulting bit stream to generate soft output values. The MIMO demapping and MAP decoding processes exchange likelihood information to improve the bit error rate performance over several iterations of demapping/decoding.

US Patent:

7580451, Aug 25, 2009

Filed:

Oct 5, 2006

Appl. No.:

11/543459

Inventors:

Albert M. Chan - Brighton MA, US
Jon Feldman - New York NY, US
Raghavendra Madyastha - Arlington MA, US
Piotr Indyk - Cambridge MA, US
David Karger - Cambridge MA, US

Assignee:

Vanu, Inc. - Cambridge MA

International Classification:

H04B 1/707
H04J 13/04

US Classification:

375150, 375142, 375147, 370209

Abstract:

Methods, systems, devices, and computer program products for decoding of Walsh codewords are disclosed.

US Patent:

20010023317, Sep 20, 2001

Filed:

Feb 23, 2001

Appl. No.:

09/791937

Inventors:

Albert Chan - Flushing NY, US

International Classification:

A61B005/04
A61M005/32

US Classification:

600/393000, 604/272000

Abstract:

This invention provides a needle with electrodes for delivery of nucleic acid or therapeutic agents for medical use in gene therapy. This invention also provides an apparatus which has one injection needle in the middle and two electrode needles on each side of the injection needle. Finally, this invention provides methods for delivering the nucleic acid using said needle or apparatus.

US Patent:

45492883, Oct 22, 1985

Filed:

Dec 20, 1982

Appl. No.:

6/450837

Inventors:

Albert Y. Chan - River Vale NJ

Assignee:

North American Philips Corporation - New York NY

International Classification:

G11B 700

US Classification:

369 48

Abstract:

Optical data recording apparatus which enhances a playback signal by comparing the lengths of the lands on a recording medium with the lengths of the pits on it and changes the playback signal to represent equality between such lengths.

Author:

Albert Chan

ISBN #:

0765608286