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公开(公告)号：DE60336903D1
公开(公告)日：2011-06-09
申请号：DE60336903
申请日：2003-07-18
Applicant: QUALCOMM INC
Inventor： JAYARAMAN SRIKANT , FERNANDEZ CORBATON IVAN JESUS , SMEE JOHN E
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公开(公告)号：MX2011001436A
公开(公告)日：2011-03-15
申请号：MX2011001436
申请日：2009-08-07
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , MALLADI DURGA PRASAD , HOU JILEI , GHADY NAVID HASSANPOUR , MALLIK SIDDHARTHA
Abstract: Se describen técnicas para soportar transmisiones de múltiple entrada múltiple salida (MIMO) distribuidas. En un diseño, un equipo de usuario (UE) determina estimaciones para múltiples celdas y reporta la designación de canal. El UE después recibe una transmisión de datos enviada por múltiples celdas hasta el UE de acuerdo con las estimaciones de canal. La transmisión de datos puede incluir por lo menos una corriente de datos y cada corriente de datos puede enviarse por una celda por las múltiples celdas hasta el UE. En otro diseño, un UE determina la primera y segunda estimación de canal de la primera y segunda celdas, respectivamente, y reporta las estimaciones de canal. El UE entonces recibe una primera transmisión de datos enviada por la primera celda hasta el UE de acuerdo con la primera estimación de canal. El UE también recibe una segunda transmisión de datos enviada por la segunda celda hasta el otro UE y se dirige lejos del UE de acuerdo con la segunda estimación de canal.
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公开(公告)号：CA2491732C
公开(公告)日：2010-06-01
申请号：CA2491732
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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公开(公告)号：DE60233581D1
公开(公告)日：2009-10-15
申请号：DE60233581
申请日：2002-09-24
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , FERNANDEZ-CORBATON IVAN JESUS , JAYARAMAN SRIKANT
Abstract: Systems and methods according to the present invention are described for adjusting the number of taps in an adaptive equalizer over time as the rate of change of a communications channel varies. The number of taps or "equalizer length" is adjusted based on an estimate of the Doppler frequency between the devices communicating over a channel. The Doppler frequency is reflective of the rate of change of the communications channel. Greater Doppler frequencies indicate a more quickly varying channel, and vice versa. It is therefore desirable to change the equalizer length (by adding or dropping taps) based on a measurement of the Doppler frequency. Equalizer length is increased as the Doppler frequency decreases. Conversely, equalizer length is decreased as the Doppler frequency increases. This enables the equalizer to achieve a better compromise between the competing goals of adaptation speed (less taps) and ISI reduction (more taps).
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公开(公告)号：AU2004204911B2
公开(公告)日：2009-06-25
申请号：AU2004204911
申请日：2004-01-07
Applicant: QUALCOMM INC
Inventor： WALTON JAY RODNEY , SMEE JOHN E , MALLADI DURGA PRASAD
Abstract: Pilot transmission schemes suitable for use in wireless multi-carrier (e.g., OFDM) communication systems. These pilot transmission schemes may utilize frequency, time, or both frequency and time orthogonality to achieve orthogonality among the pilots transmitted by multiple base stations on the downlink. Frequency orthogonality is achieved by transmitting pilots on disjoint sets of subbands. Time orthogonality is achieved by transmitting pilots using different orthogonal codes (e.g., Walsh codes). The pilots may also be scrambled with different scrambling codes, which are used to randomize pilot interference and to enable identification of the transmitters of these pilots. Pilot interference cancellation may be performed to improve performance since subbands used for data transmission by one transmitter may also be used for pilot transmission by another transmitter. Pilot interference is estimated and then subtracted from received symbols to obtain pilot-canceled symbols having improved quality.
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Patent Agency Ranking
公开(公告)号：DE60214847T2
公开(公告)日：2007-10-04
申请号：DE60214847
申请日：2002-05-31
Applicant: QUALCOMM INC
Inventor： CORBATON IVAN JESUS , SMEE JOHN E , JAYARAMAN SRIKANT
Abstract: Method and apparatus that compensates for overestimation of channel SINR due to overfitting of an adaptive equalizer to the pilot portion of a received frame. The SINR of a wireless channel is estimated by adapting an adaptive equalizer using the pilot portion of the frame, applying the adaptive equalizer to a non-pilot portion of the frame, determining a parameter using the adaptive equalizer output, and estimating the SINR of the wireless channel using the parameter. The parameter can include, for example, the mean square error (MSE) or the bias of the equalizer output. The accuracy of the SINR estimate according to this aspect of the present invention is thereby improved (as compared to a SINR estimate based on parameters calculated during the pilot interval) because the adaptive equalizer is not overfit to the control or data portions of the frame.
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公开(公告)号：NO20073238A
公开(公告)日：2007-09-21
申请号：NO20073238
申请日：2007-06-22
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , HOU JILEI , PFISTER HENRY DAVID , TOMASIN STEFANO
CPC classification number: H04W52/146 , H04B1/7103 , H04B2201/70701
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公开(公告)号：NO20073237L
公开(公告)日：2007-09-21
申请号：NO20073237
申请日：2007-06-22
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , HOU JILEI , PFISTER HENRY DAVID , TOMASIN STEFANO
Abstract: A method is provided comprising generating data samples of received signals; demodulating the data samples to provide recovered symbols; deinterleaving the recovered symbols; decoding the recovered symbols to recover decoded data bits transmitted by an access terminal; encoding, interleaving and modulating the decoded data bits to form samples from the access terminal; and removing or cancelling a contribution of the access terminal from the data samples. Corresponding electronic hardware, software module and storage medium are also provided.
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公开(公告)号：NO20073236L
公开(公告)日：2007-09-21
申请号：NO20073236
申请日：2007-06-22
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , HOU JILEI , PFISTER HENRY DAVID , TOMASIN STEFANO
Abstract: A method and system for interference cancellation (IC). One aspect relates to traffic interference cancellation. Another aspect relates to joint IC for pilot, overhead and data. Another aspect relates to improved channel estimation. Another aspect relates to adaptation of transmit subchannel gains.
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公开(公告)号：NO20073236A
公开(公告)日：2007-09-21
申请号：NO20073236
申请日：2007-06-22
Applicant: QUALCOMM INC
Inventor： SMEE JOHN E , HOU JILEI , PFISTER HENRY DAVID , TOMASIN STEFANO
CPC classification number: H04B1/7103
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