Joseph H Cavallaro

US Patent:

6529495, Mar 4, 2003

Filed:

May 24, 1999

Appl. No.:

09/317333

Inventors:

Joseph R. Cavallaro - Pearland TX
Gang Xu - Houston TX

Assignee:

Nokia Telecommunications, Oy

International Classification:

H04B 7216

US Classification:

370342, 375148, 375150

Abstract:

A multistage detector is disclosed that maximizes computation power while minimizing system delay. The differencing multistage detector receives signals from a plurality of users in a cell of a communications system and reduces the effect of multiple access interference to a signal from a desired user caused by interference from other users in the cell. The differencing multistage detector includes a plurality of stages, each stage including an interference canceller for removing intra-cell interference caused by the other users in the cell and producing an estimation output vector, wherein except for a first stage, the estimation output vector of a current stage is based on both a decision of the interference canceller of the current stage and the output from an interference canceller of a previous stage. The estimation output vector of a current stage is produced by combining the output from an interference canceller of a previous stage and the decision of the interference canceller of the current stage. Except for the first stage each interference canceller calculates an estimate of multi-user interference by computing a product of a cross-correlation of the received signals and a difference signal thereby reducing the number of multiplication operations required.

US Patent:

8027404, Sep 27, 2011

Filed:

Feb 5, 2008

Appl. No.:

12/025971

Inventors:

Kiarash Amiri - Houston TX, US
Raghavendar Mysore Rao - Austin TX, US
Christopher H. Dick - San Jose CA, US
Joseph R. Cavallaro - Pearland TX, US

Assignee:

Xilinx, Inc. - San Jose CA

International Classification:

H04B 7/02

US Classification:

375267, 375299, 375347

Abstract:

A circuit detects symbols communicated between multiple transmitting antennas and multiple receiving antennas (MIMO). Distance blocks are coupled in a sequence according to an ordering of the transmitting antennas. The respective distance block associated with each transmitting antenna determines a distance value for each pairing of one or more candidates and a symbol in a constellation. A respective selector block is coupled between each successive pair of distance blocks in the sequence. The respective selector block selects the one or more candidates for the successive distance block as a limited number of the pairings having smaller ones of the distance values. A limit block coupled to the selector blocks provides the limited number to each selector block. An identifier block selects the pairing having a smaller one of the distance values from the last distance block in the sequence.

US Patent:

8040981, Oct 18, 2011

Filed:

Jul 10, 2008

Appl. No.:

12/170468

Inventors:

Kiarash Amiri - Houston TX, US
Christopher H. Dick - San Jose CA, US
Raghavendar Mysore Rao - Austin TX, US
Joseph R. Cavallaro - Pearland TX, US

Assignee:

XILINX, Inc. - San Jose CA

International Classification:

H04L 27/06

US Classification:

375340, 375267, 375347

Abstract:

Circuits are provided for detecting symbols transmitted from multiple transmitting antennas to multiple receiving antennas. A circuit includes distance blocks, selectors, and an identifier block. Each distance-block includes at least one sub-block, and each sub-block inputs a candidate for a corresponding transmitting antenna. The sub-block determines partial distances for pairings of the candidate and each symbol in a constellation from a partial distance of the candidate and signals received at the receiving antennas. At least one selector assigns each pairing for each candidate for a corresponding transmitting antenna to a bin having a range that includes the partial distance of the pairing. The selector selects candidates for a successive transmitting antenna from the bins having the smaller ranges. The identifier block selects a final candidate that is one of the pairings for a last transmitting antenna having a smaller partial distance.

US Patent:

8059761, Nov 15, 2011

Filed:

Jul 10, 2008

Appl. No.:

12/170474

Inventors:

Kiarash Amiri - Houston TX, US
Christopher H. Dick - San Jose CA, US
Raghavendar Mysore Rao - Austin TX, US
Joseph R. Cavallaro - Pearland TX, US

Assignee:

Xilinx, Inc. - San Jose CA

International Classification:

H04L 27/06

US Classification:

375340

Abstract:

Circuits detect communications from multiple transmitting antennas to multiple receiving antennas. A respective first block for each non-initial transmitting antenna determines partial distances for pairings of a first candidate and a quadrature-phase amplitude. A respective second block for the initial transmitting antenna determines partial distances for combinations of phase amplitudes. A respective second block for each non-initial transmitting antenna determines partial distances for pairings of a second candidate and an in-phase amplitude. A respective first selector for each non-initial transmitting antenna selects the first candidates from the pairings for the respective second block having smaller partial distances. A respective second selector for each non-initial transmitting antenna selects the second candidates from the pairings for the respective first block having smaller partial distances. An identifier circuit selects a final candidate with a smaller partial distance from the pairings of the respective second block for the last transmitting antenna.

US Patent:

8139512, Mar 20, 2012

Filed:

May 30, 2008

Appl. No.:

12/156211

Inventors:

Gilles Charbit - Hampshire, GB
Jorma O. Lilleberg - Oulu, FI
Joseph R. Cavallaro - Pearland TX, US
Marjan Karkooti - Bryan TX, US

Assignee:

Nokia Corporation - Espoo

International Classification:

H04B 7/14

US Classification:

370279, 455 7, 455 15, 455 16

Abstract:

A source sends an encoded data block during a first time interval to a destination and to a relay. The source sends additional parity bits for the encoded data block during a second time interval. The relay partially decodes that encoded data block to a process-defined end point (typically only a partial decoding), such as a fixed number of decoding iterations. After partial decoding the relay forms a modified data block having corrected information bits and the parity bits of the block it received, and sends the modified data block to the destination, during the second time interval. The destination decodes to a results-defined end point the modified data block it received from the relay using the additional parity bits it received from the source. If that end-point cannot be reached, the destination may begin anew decoding the original encoded data block it received from the source.

US Patent:

8219876, Jul 10, 2012

Filed:

Oct 24, 2007

Appl. No.:

11/977644

Inventors:

Predrag Radosavljevic - Houston TX, US
Marjan Karkooti - Bryan TX, US
Alexandre de Baynast - Aachen, DE
Joseph R. Cavallaro - Pearland TX, US

Assignee:

Core Wireless Licensing, S.a.r.l. - Plano TX

International Classification:

H03M 13/00
G11C 29/00

US Classification:

714758, 714763

Abstract:

The invention relates to low density parity check decoding. A method for decoding an encoded data block is described. Encoded data block comprising data sub-blocks are stored. Decoding is performed in a pipelined manner using an irregular, block-structured parity check matrix, where at least two data sub-block matrices of the parity check matrix are read from and written in each of a plurality of clock cycles. The reading and writing of the data sub-blocks is evenly distributed between at least two area of a memory. The decoding is performed with shift values which eliminate cycles at or below a predetermined threshold length. An apparatus, computer program product and device are also described.

US Patent:

8401115, Mar 19, 2013

Filed:

Mar 11, 2008

Appl. No.:

12/045786

Inventors:

Kiarash Amiri - Houston TX, US
Raghavendar Mysore Rao - Austin TX, US
Christopher H. Dick - San Jose CA, US
Joseph R. Cavallaro - Pearland TX, US

Assignee:

Xilinx, Inc. - San Jose CA

International Classification:

H04L 27/00

US Classification:

375299, 375265, 375316, 375340, 375347, 375267

Abstract:

A circuit detects symbols transmitted from multiple transmitting antennas to multiple receiving antennas. A distance block for an initial transmitting antenna in an ordering of the transmitting antennas determines a distance value for each symbol in a constellation. A selector block selects a limited number of candidates for the initial transmitting antenna from the symbols having smaller distance values. For each first and successive second transmitting antenna in the ordering, a distance-selector block selects a candidate for the second transmitting antenna for each candidate for the first transmitting antenna. The candidate for the second transmitting antenna is a pairing having a smaller distance value among the pairings of the candidate for the first transmitting antenna and the symbols. An identifier block selects a last candidate having a smaller distance value among the candidates for a last transmitting antenna in the ordering. The last candidate includes the detected symbols.

US Patent:

8477862, Jul 2, 2013

Filed:

Dec 2, 2010

Appl. No.:

12/959007

Inventors:

Yang Sun - Houston TX, US
Joseph R. Cavallaro - Pearland TX, US
Jorma Lilleberg - Oulu, FI

Assignee:

Nokia Corporation - Espoo

International Classification:

H04L 5/12

US Classification:

375265, 375260, 375262, 375340, 375341

Abstract:

An apparatus for trellis-based detection in a communication system including a processor and memory having computer program code configured to construct a trellis representing a transmitted signal formed from a plurality of symbols, each having a constellation size, transmitted by a number of transmit antennas, and form a log likelihood ratio at nodes of the trellis as a log-sum of a number of exponential terms including a priori information corresponding to a hypothesized transmitted bit value of the plurality of symbols. The number of exponential terms is limited by a number of most likely paths of the trellis extending from each node of the trellis and the constellation size. The processor and memory including computer program code are configured to form a list at each node of the trellis of a size limited to the number of the most likely paths of the trellis extending from each node.