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公开(公告)号：NO20050863L
公开(公告)日：2005-02-17
申请号：NO20050863
申请日：2005-02-17
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , JAYARAMAN SRIKANT , CORBATON IVAN JESUS FERNANDEZ
Abstract: A method and apparatus for a decision feedback equalizer wherein a correction term is used to compensate for slicer errors, thus avoiding error propagation. Filter coefficients for the equalizer are selected so as to minimize a cost function for the equalizer, including a correction term as a function of the energy of the filter coefficients. The equalizer includes a coefficient generator responsive to the correction term. One embodiment estimates a transmitted symbol from a received sample as a function of Signal-to-Interference and Noise Ratio (SINR) of the received sample. The received sample is quantized and mapped to a region of a grid overlaid on the transmitted symbol constellation. The region may correspond to a symbol estimate value or may be processed further to obtain a symbol estimate value.
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公开(公告)号：NO20050863A
公开(公告)日：2005-02-17
申请号：NO20050863
申请日：2005-02-17
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , JAYARAMAN SRIKANT , CORBATON IVAN JESUS FERNANDEZ
CPC classification number: H04L25/03057 , H04L25/03267 , H04L2025/0349 , H04L2025/03496 , H04L2025/03611
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公开(公告)号：NO20050005L
公开(公告)日：2005-01-17
申请号：NO20050005
申请日：2005-01-03
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , JAYARAMAN SRIKANT , FERNANDEZ-CORBATON IVAN JESUS
Abstract: Techniques for selecting either a DFE or an LE for use to equalize a received signal, and for quickly and efficiently determining the coefficients for the selected equalizer. In an embodiment, a method is provided whereby the DFE is initially adapted based on the received signal and a particular adaptive algorithm (e.g., the LMS algorithm) for an initial time period. A quality metric is then determined for an output of the DFE. The DFE is selected for use if the quality metric is better than a threshold value, and the LE is selected otherwise. If the LE is selected, then the initial values for the coefficients of the LE may be derived based on the coefficients of a feed-forward filter and a feedback filter for the DFE, and the LE coefficients may further be adapted for an additional time period prior to its use to equalize the received signal.
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公开(公告)号：NO20050005A
公开(公告)日：2005-01-17
申请号：NO20050005
申请日：2005-01-03
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , JAYARAMAN SRIKANT , FERNANDEZ-CORBATON IVAN JESUS
CPC classification number: H04L1/188 , H04L1/20 , H04L25/03038 , H04L25/03057 , H04L2025/03573 , H04L2025/03617
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85.发明专利
公开(公告)号：CA2517008A1
公开(公告)日：2004-09-10
申请号：CA2517008
申请日：2004-02-23
Applicant: QUALCOMM INC
Inventor： FERNANDEZ-CORBATON IVAN JESUS , SMEE JOHN E , JAYARAMAN SRIKANT
Abstract: Techniques for performing equalization of multiple signals received by a terminal in soft handoff with multiple base stations. The received signal at the terminal is conditioned and digitized to provide a stream of received samples (y m ), which is then equalized/filtered (410) with multiple sets of coefficients to provide multiple streams of transmit chip estimates (X k ). One set of coefficients (f k ) is provided for each base station and is used to provide a corresponding stream of transmit chip estimates. The multiple streams of transmit chip estimates are further processed (420) to provide multiple streams of data symbol estimates (d k ), one stream of data symbol estimates for each base station. The multiple streams of data symbol estimates are then scaled (430) with multiple scaling factors (± k ) and combined (432) to provide a stream of combined data symbol estimates (d k ). The processing for the multiple base stations may be performed by a single hardware unit in a time division multiplexed manner.
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Patent Agency Ranking86.发明专利
公开(公告)号：HK1056796A1
公开(公告)日：2004-02-27
申请号：HK03109045
申请日：2003-12-11
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , JALALI AHMAD
IPC: H04B1/7115 , H04B3/06 , H04B7/005 , H04B7/08 , H04L25/03
Abstract: In a method for achieving higher S/N, one or more signals are received and processed to provide one or more streams of samples. In a first processing scheme, the sample stream(s) are equalized and combined within an equalizer to generate symbol estimates, which maybe subsequently processed (e.g. despread and decovered) to provide a first stream of recovered symbols. The sample stream(s) may be equalized prior to being combined. In this case, each sample stream is filtered with a set of coefficients and may be scaled with a scaling factor. The scaled samples for all streams are then combined to generate the symbol estimates. Alternatively, the sample stream(s) may be combined prior to being equalized. In this case, each sample stream is scaled by a scaling factor. The scaled samples for all streams are then combined to generate summed samples that are further filtered with a set of coefficients to generate the symbol estimates. The sample stream(s) may also be processed by a second processing scheme with one or more rake receivers to provide a second stream of recovered symbols. The signal quality for each processing scheme can be estimated and used to select either the first or second processing scheme.
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公开(公告)号：AU2003256622A1
公开(公告)日：2004-02-16
申请号：AU2003256622
申请日：2003-07-18
Applicant: QUALCOMM INC
Inventor： FERNANDEZ-CORBATON IVAN JESUS , SMEE JOHN E , JAYARAMAN SRIKANT
Abstract: A non-parametric matched filter receiver that includes a digital (e.g., FIR) filter and a channel estimator. The channel estimator (1) determines the timing to center the digital filter, (2) obtains the characteristics of the noise in received samples, (3) estimates the system response for the samples using a best linear unbiased (BLU) estimator, a correlating estimator, or some other type of estimator, and (4) derives a set of coefficients for the digital filter based on the estimated system response and the determined noise characteristics. The correlating estimator correlates the samples with their known values to obtain the estimated system response. The BLU estimator pre-processes the samples to whiten the noise, correlates the whitened samples with their known values, and applies a correction factor to obtain the estimated system response. The digital filter then filters the samples with the set of coefficients to provide demodulated symbols.
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88.发明专利
公开(公告)号：ES2791527T3
公开(公告)日：2020-11-04
申请号：ES10012069
申请日：2004-01-07
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , WALTON JAY RODNEY , MALLADI DURGA PRASAD
Abstract: Un procedimiento para transmitir un piloto en un enlace descendente en un sistema de comunicación inalámbrica de múltiples portadoras (100) que comprende: generar símbolos de piloto para la transmisión en un primer conjunto de subbandas, en el que el primer conjunto de subbandas se utiliza para la transmisión de piloto mediante una primera entidad transmisora y está separado de un segundo conjunto de subbandas utilizado para la transmisión de piloto mediante una segunda entidad transmisora, y en el que cada par de subbandas adyacentes en el primer conjunto abarca un intervalo de frecuencias que es menor o igual que un ancho de banda de coherencia de un canal inalámbrico en el sistema; procesar los símbolos de piloto para obtener una señal piloto que tenga los símbolos de piloto incluidos en el primer conjunto de subbandas; y transmitir la señal piloto desde la primera entidad transmisora.
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89.发明专利
公开(公告)号：AU2009279485C1
公开(公告)日：2014-04-10
申请号：AU2009279485
申请日：2009-08-07
Applicant: QUALCOMM INC
Inventor： HOU JILEI , SMEE JOHN E , MALLADI DURGA PRASAD , HASSANPOUR GHADY NAVID , MALLIK SIDDHARTHA
Abstract: Techniques for supporting distributed multiple-input multiple-output (MIMO) transmissions are described. In one design, a user equipment (UE) determines channel estimates for multiple cells and reports the channel estimates. The UE thereafter receives a data transmission sent by the multiple cells to the UE based on the channel estimates. The data transmission may include at least one data stream, and each data stream may be sent by one cell or the multiple cells to the UE. In another design, a UE determines first and second channel estimates for first and second cells, respectively, and reports the channel estimates. The UE then receives a first data transmission sent by the first cell to the UE based on the first channel estimate. The UE also receives a second data transmission sent by the second cell to another UE and steered away from the UE based on the second channel estimate.
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公开(公告)号：ES2368120T3
公开(公告)日：2011-11-14
申请号：ES08010035
申请日：2003-07-18
Applicant: QUALCOMM INC
Inventor： JAYARAMAN SRIKANT , FERNANDEZ CORBATON IVAN JESUS , SMEE JOHN E
IPC: H04L25/03
Abstract: Un procedimiento para estimar un símbolo transmitido utilizando un seccionador flexible, mapeándose el símbolo transmitido con un mapa de constelación ψ, el procedimiento comprendiendo: recibir una muestra; estimar Relación de Señal a Interferencia más Ruido SINR de la muestra; estimar el símbolo transmitido en base al SINR y a la muestra, caracterizado porque la estimación del símbolo transmitido comprende: calcular la varianza de la muestra recibida definida por la relación: y evaluar una media condicional como: en el que Y representa la muestra de entrada al seccionador flexible y y representa los símbolos transmitidos que pertenecen al mapa de constelación ψ.
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