| Patent application number | Description | Published |
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| 20080253487 | ADAPTIVE PILOT AND DATA SYMBOL ESTIMATION - Techniques for performing adaptive channel estimation are described. A receiver derives channel estimates for a wireless channel based on received pilot symbols and at least one estimation parameter. The receiver updates the at least one estimation parameter based on the received pilot symbols. The at least one estimation parameter may be for an innovations representation model of the wireless channel and may be updated based on a cost function with costs defined by prediction errors. In one design, the receiver derives predicted pilot symbols based on the received pilot symbols and the at least one estimation parameter, determines prediction errors based on the received pilot symbols and the predicted pilot symbols, and further derives error gradients based on the prediction errors. The receiver then updates the at least one estimation parameter based on the error gradients and the prediction errors, e.g., if a stability test is satisfied. | 10-16-2008 |
| 20100046595 | SEMI-COHERENT TIMING PROPAGATION FOR GERAN MULTISLOT CONFIGURATIONS - A method for estimating timing in a wireless communication comprises the steps of receiving a plurality of symbol bursts corresponding to a plurality of time slots and selecting a subset of symbols from a first symbol burst of the plurality of symbol bursts. The subset comprises a first midamble symbol. The method further comprises the steps of calculating, for each symbol in the subset, a corresponding midamble estimation error, and determining the lowest calculated midamble estimation error to determine a timing for the first symbol burst. The method further comprises the steps of processing the first symbol burst utilizing the timing determined for the first symbol burst, and processing a second symbol burst of the plurality of symbol bursts utilizing the timing determined for the first symbol burst. | 02-25-2010 |
| 20100046660 | INTERFERENCE CANCELLATION UNDER NON-STATIONARY CONDITIONS - A method for timing and frequency synchronization in a wireless system is provided. The method comprises the steps of receiving a burst of symbols, selecting a subset of the burst of symbols, iteratively adjusting the subset of the burst of symbols by a plurality of timing offsets and calculating, for each timing offset, a first performance metric corresponding to the adjusted subset. The method further comprises the steps of determining one of the plurality of timing offsets to be a preferred timing offset based upon the first performance metric thereof, iteratively rotating the subset of the burst of symbols by a plurality of frequency offsets and calculating, for each frequency offset, a second performance metric corresponding to the rotated subset, and determining one of the plurality of frequency offsets to be a preferred frequency offset based upon the second performance metric thereof. | 02-25-2010 |
| 20100046682 | ENHANCED GERAN RECEIVER USING CHANNEL INPUT BEAMFORMING - A method for suppressing interference in a wireless communication is provided. The method comprises receiving a burst of symbols, generating a plurality of timing hypotheses for the burst of symbols, and calculating, for each timing hypothesis, a plurality of weights for an interference suppression filter based upon a subset of the burst of symbols. The method further comprises, for each timing hypothesis, filtering the subset of the burst of symbols using the interference suppression filter with the corresponding plurality of weights, and selecting one of the plurality of timing hypotheses corresponding to a selection criteria. The method further comprises equalizing and decoding the filtered burst of symbols based upon the selected one of the plurality of timing hypotheses. | 02-25-2010 |
| 20100278035 | METHOD AND SYSTEM FOR MULTI-USER DETECTION USING TWO-STAGE PROCESSING - Systems and methods for multi-user detection in a multiple access system are provided. In one aspect, an apparatus is provided. The apparatus comprises a processing unit configured to process received chips into received symbols for a plurality of users and a computation unit configured to compute a multi-user matrix using a Hadamard matrix, wherein the multi-user matrix relates user symbols for the plurality of users to the received symbols. The apparatus further comprises a detection unit configured to detect the user symbols for the plurality of users using the received symbols and the computed multi-user matrix. | 11-04-2010 |
| 20100278167 | METHOD AND SYSTEM FOR DATA-AIDED CHANNEL ESTIMATION - Systems and methods for data-aided channel estimation are provided. In one aspect of the disclosure, a channel estimation apparatus is provided. The apparatus comprises a first processing unit configured to process received chips into received symbols and a detection unit configured to detect user symbols from the received symbols. The apparatus further comprises a second processing unit configured to process the detected user symbols into estimated transmit chips and a channel computation unit configured to estimate a channel based on the estimated transmit chips and the received chips. | 11-04-2010 |
| 20100278216 | METHOD AND SYSTEM FOR INTER-CELL INTERFERENCE CANCELLATION - Systems and methods for inter-cell interference cancellation are provided. In one aspect of the disclosure, an apparatus is provided. The apparatus comprises a cell computation unit configured to compute receive chips for a first interfering cell and a subtraction unit configured to remove the computed receive chips for the first interfering cell from received chips at a receiver. The apparatus further comprises a processing unit configured to process the received chips with the computed receive chips for the first interfering cell removed into received symbols and a detection unit configured to detect user symbols for a target cell from the received symbols. | 11-04-2010 |
| 20100278217 | METHOD AND SYSTEM FOR MULTI-USER DETECTION USING TWO-STAGE PROCESSING - Systems and methods for multi-user detection are provided. In one aspect of the disclosure, an apparatus is provided. The apparatus comprises a processing unit configured to process a plurality of received chips into a plurality of received symbols for a plurality of users. The apparatus further comprises a computation unit configured to compute a multi-user matrix relating a plurality of user symbols for the plurality of users to the plurality of received symbols and a detection unit configured to detect the plurality of user symbols for the plurality of users using the computed multi-user matrix and the plurality of received symbols. | 11-04-2010 |
| 20100278218 | METHOD AND SYSTEM FOR MULTI-USER INTERFERENCE CANCELLATION - Systems and methods for multi-user interference cancellation are provided. In one aspect of the disclosure, an apparatus is provided. The apparatus comprises a processing unit configured to process received chips into received symbols for a plurality of users and a detection unit configured to detect user symbols from the received symbols. The apparatus also comprises an interference cancellation unit configured to compute multi-user interference using the detected user symbols and to remove the computed multi-user interference from the received symbols. The apparatus further comprises a redetection unit configured to redetect user symbols from the received symbols with the computed multi-user interference removed. | 11-04-2010 |
| 20100278284 | METHOD AND SYSTEM FOR SYMBOL DETECTION USING SUB-CONSTELLATIONS - Systems and methods for symbol detection using sub-constellations are provided. In one aspect of the disclosure, an apparatus is provided. The apparatus comprises a processing unit configured to process received chips into received symbols for a plurality of users, a first detection unit configured to detect first components of user symbols for the plurality of users based on the received symbols and a computation unit configured to compute a portion of the received symbols due to the first components of the user symbols. The apparatus further comprises a second detection unit configured to detect second components of the user symbols based on the received symbols with the computed portion removed and a combining unit configured to detect the user symbols by combining the first components of the user symbols with the respective second components of the user symbols. | 11-04-2010 |
| 20100309956 | METHOD AND SYSTEM FOR INTERFERENCE CANCELLATION - Systems and methods for interference cancellation at a receiver in a wireless communication system are provided. In one aspect, a method for interference cancellation is provided. The method comprises providing total received chips received from a plurality of cells. The method also comprises successively estimating received chips for each of the plurality of cells in a plurality of iterations, wherein each of the plurality of iterations after a first iteration comprises canceling previously estimated received chips for one or more of the plurality of cells from the total received chips, and estimating received chips for one of the plurality of cells using the total received chips with the previously estimated received chips for the one or more of the plurality of cells cancelled out. | 12-09-2010 |
| 20100310026 | ITERATIVE INTERFERENCE CANCELLATION RECEIVER - A method for suppressing interference in a wireless communication comprises receiving a burst of symbols, filtering the burst of symbols using an interference suppression filter with a first plurality of weights, decoding the filtered burst of symbols to generate data corresponding to the burst of symbols, encoding the data to generate a re-encoded burst of symbols, calculating a second plurality of weights for the interference suppression filter based upon the re-encoded burst of symbols, filtering the re-encoded burst of symbols using the interference suppression filter with the second plurality of weights, and decoding the filtered re-encoded burst of symbols. | 12-09-2010 |
| 20110051859 | SYMBOL ESTIMATION METHODS AND APPARATUSES - A novel symbol estimation method produces intersymbol interference free symbols by detecting interfering symbols in an interfering channel. A channel estimate is refined for additional improvements. The method can lends itself as a serial or parallel algorithm implementation. The symbol estimation method includes using an initial estimate of received symbols and calculating a refined estimate of the received symbols using a channel estimate. The refined estimate is calculated by performing parameterization of intersymbol interference by symbols other than the symbol being refined and selecting a refined value for the symbol being refined by evaluating an optimization function. Symbol estimates are refined in multiple iterations, until a predetermined iteration termination criterion is met. Parameterization of ISI contribution of other symbols results in reduced computation by reducing total number of unknown variables in the refinement operation. | 03-03-2011 |
| 20110051864 | MULTI-STAGE INTERFERENCE SUPPRESSION - A multi-stage interference suppression receiver includes a short equalizer section configured to operate on a first portion of a received signal received over a channel to produce a first equalized signal and a first estimate of the channel, a channel estimator section configured to operate on the first equalized signal to produce a second equalized signal, the channel estimator section comprising a linear estimator and a non-linear estimator, a long equalizer section configured to operate on a second portion of the received signal to produce a first estimate of symbols in the received signal and a second estimate of the channel and an interference canceller section configured to operate on the first estimate of symbols in the received signal to generate a second estimate of symbols in the received signal based on, at least in part, the second estimate of the channel. | 03-03-2011 |
