Dov S Rosenfeld

US Patent:

6690747, Feb 10, 2004

Filed:

Jun 6, 2001

Appl. No.:

09/877807

Inventors:

Paul Petrus - Sunnyvale CA
Alain M. Chiodini - Mountain View CA
Mitchell D Trott - Mountain View CA
David M. Parish - Los Altos CA
Michael Youssefmir - Palo Alto CA
Dov Rosenfeld - Oakland CA

Assignee:

ArrayComm, Inc. - San Jose CA

International Classification:

H04L 2714

US Classification:

375324, 375326, 370310, 343893

Abstract:

A method for generating a reference signal from a modulated signal transmitted to a communications station that includes an array of antenna elements and spatial processing means including: separating from the signals received at the antenna elements a copy signal corresponding to the signal transmitted by a particular remote station using an initial spatial weight vector corresponding to the particular remote station; determining from the terminal copy signal a reference signal having substantially the same frequency offset and time alignment as the received antenna signals; and computing a new spatial weight vector by optimizing a cost function, the cost function using the received antenna signals and the reference signal. For demodulation, the method further includes extracting the symbols of the modulated signal.

US Patent:

7471840, Dec 30, 2008

Filed:

Aug 18, 2004

Appl. No.:

10/922508

Inventors:

John A. Toebes - Cary NC, US
Wen-hsiung Chen - Sunnyvale CA, US
Fang Wu - Pleasanton CA, US
Dov Rosenfeld - Oakland CA, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

G06K 9/36

US Classification:

382245

Abstract:

A method, apparatus, and carrier medium to encode a series of quantized transform coefficients. The method includes identifying events that each includes a run of zero-valued coefficients preceding a run of one or more non-zero-valued coefficients, and for each such event, jointly encoding the run lengths of the preceding run of zero-valued coefficients and the following run of non-zero-valued coefficients with a codeword, such that for at least some events, relatively more likely-to-occur pairs of runlengths are encoded by a shorter codeword than relatively less likely-to-occur runlengths. The method further includes encoding each amplitude in the run of consecutive non-zero-valued coefficients, and encoding the signs of such coefficients. The method is applicable to encoding a region in the series where there is likely to be a cluster of non-zero-valued coefficients.

US Patent:

7680349, Mar 16, 2010

Filed:

Mar 20, 2006

Appl. No.:

11/385183

Inventors:

Wen-hsiung Chen - Sunnyvale CA, US
Fang Wu - Pleasanton CA, US
John A. Toebes - Cary NC, US
Dov Rosenfeld - Oakland CA, US
Gregory D. Pelton - Raleigh NC, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

G06K 9/36

US Classification:

382246, 382245

Abstract:

Coding quantized transform coefficients as occur in image compression combines a position identifying method to identify the relative position of clusters of consecutive non-zero-valued coefficients, an amplitude event identifying method to identify amplitude events in the clusters of non-zero-valued coefficients, and a coding method to code the position events, amplitude events, and signs of the amplitudes in the clusters. The method is particularly applicable to a series of quantized transform coefficients where clusters are likely to occur.

US Patent:

7796825, Sep 14, 2010

Filed:

Feb 16, 2007

Appl. No.:

11/675773

Inventors:

Wen-hsiung Chen - Sunnyvale CA, US
Dov Rosenfeld - Oakland CA, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

G06K 9/36

US Classification:

382232

Abstract:

For data compressed using the first compression method that includes codewords generated by variable length coding sets of quantized transform coefficients using a first variable length coding method, decoding the codewords to create ordered sets of quantized transform coefficients, each created set forming an ordered series of quantized transform coefficients, and re-encoding the created ordered sets of quantized transform coefficients using a second variable length coding method to produce a re-coded set of codewords. The second variable length coding method produces shorter codewords, on average, than the first variable length coding method. The decoding and re-encoding is a lossless process such that no additional quantization or other errors are introduced to the received data by the method.

US Patent:

7912306, Mar 22, 2011

Filed:

Nov 25, 2009

Appl. No.:

12/626409

Inventors:

Wen-hsiung Chen - Sunnyvale CA, US
Fang Wu - Pleasanton CA, US
John A. Toebes - Cary NC, US
Dov Rosenfeld - Oakland CA, US
Gregory D. Pelton - Raleigh NC, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

G06K 9/36

US Classification:

382246, 382245

Abstract:

Coding quantized transform coefficients as occur in image compression combines a position identifying method to identify the relative position of clusters of consecutive non-zero-valued coefficients, an amplitude event identifying method to identify amplitude events in the clusters of non-zero-valued coefficients, and a coding method to code the position events, amplitude events, and signs of the amplitudes in the clusters. The method is particularly applicable to a series of quantized transform coefficients where clusters are likely to occur.

US Patent:

8131096, Mar 6, 2012

Filed:

Mar 5, 2011

Appl. No.:

13/041376

Inventors:

Wen-hsiung Chen - Sunnyvale CA, US
Fang Wu - Pleasanton CA, US
John A. Toebes - Cary NC, US
Dov Rosenfeld - Oakland CA, US
Gregory D. Pelton - Raleigh NC, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

G06K 9/36

US Classification:

382246, 382245

Abstract:

Coding quantized transform coefficients as occur in image compression combines a position identifying method to identify the relative position of clusters of consecutive non-zero-valued coefficients, an amplitude event identifying method to identify amplitude events in the clusters of non-zero-valued coefficients, and a coding method to code the position events, amplitude events, and signs of the amplitudes in the clusters. The method is particularly applicable to a series of quantized transform coefficients where clusters are likely-to-occur.

US Patent:

8494295, Jul 23, 2013

Filed:

Feb 16, 2012

Appl. No.:

13/398741

Inventors:

Wen-hsiung Chen - Sunnyvale CA, US
Fang Wu - Pleasanton CA, US
John A. Toebes - Cary NC, US
Dov Rosenfeld - Oakland CA, US
Gregory D. Pelton - Raleigh NC, US

Assignee:

Cisco Technology, Inc. - San Jose CA

International Classification:

G06K 9/36

US Classification:

382246, 382245

Abstract:

Disclosed are apparatuses, computer readable storage media with instructions that carry out methods, and methods of (a) coding quantized transform coefficients as occur in image compression to form codewords, and (b) decoding a bitstream comprising the codewords. The coding combines a position identifying method to identify the relative position of clusters of consecutive non-zero-valued quantized transform coefficients, an amplitude event identifying method to identify amplitude events in the clusters of non-zero-valued quantized transform coefficients, and a coding method to code the position events, amplitude events, and signs of the amplitudes in the clusters. The coding method is particularly applicable to an ordered series of quantized transform coefficients where clusters are likely-to-occur.

US Patent:

62755439, Aug 14, 2001

Filed:

Sep 15, 1998

Appl. No.:

9/153110

Inventors:

Paul Petrus - Sunnyvale CA
Alain M. Chiodini - Mountain View CA
Mitchell D. Trott - Mountain View CA
David M. Parish - Los Altos CA
Michael Youssefmir - Palo Alto CA
Dov Rosenfeld - Oakland CA

Assignee:

ArrayComm, Inc. - San Jose CA

International Classification:

H04L 2714

US Classification:

375324

Abstract:

A method for generating a reference signal from a modulated signal transmitted to a communications station that includes an array of antenna elements and spatial processing means including: separating from the signals received at the antenna elements a copy signal corresponding to the signal transmitted by a particular remote station using an initial spatial weight vector corresponding to the particular remote station; determining from the terminal copy signal a reference signal having substantially the same frequency offset and time alignment as the received antenna signals; and computing a new spatial weight vector by optimizing a cost function, the cost function using the received antenna signals and the reference signal. For demodulation, the method further includes extracting the symbols of the modulated signal.