Patents by Inventor Ali S. Sadri

Ali S. Sadri has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20040120428
    Abstract: Briefly, in accordance with one embodiment of the invention, a channel estimator may be adapted to provide a channel estimate based at least in part on an estimated delay spread. The channel estimator may be adapted to provide a more accurate channel estimation in the event of a lower estimated delay spread. In one embodiment, the channel estimator provides a frequency domain channel estimate, and in another embodiment the channel estimator provides a time domain channel estimate.
    Type: Application
    Filed: March 5, 2003
    Publication date: June 24, 2004
    Inventors: Alexander A. Maltsev, Andrey V. Pudeyev, Ali S. Sadri
  • Patent number: 6690652
    Abstract: A WCDMA system includes a Base Station (BS) transmitter, or forward transmitter and a pilot channel that transmits control signals between the BS and a Mobile Station (MS) to reconfigure their transmitter/receiver. Reconfiguration is performed according to the prediction of the channel attenuation and the threshold set at the BS or MS based on its channel power probability density function separated into three distinct equal probable regions. In one embodiment, Seamless Rate Change (SRC)/Transmitter Power Control (TPC) logic uses the predicted channel attenuation to signal both the transmitter and the receiver in a channel to reconfigure their transmit power level according to the power density function (pdf) of the channel power and threshold level. A transmission rate is reduced when the power level is below the threshold and increased when the channel power is above threshold. The pilot channel is used to signal the mobile station and the base station.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: February 10, 2004
    Assignee: International Business Machines Corporation
    Inventor: Ali S. Sadri
  • Patent number: 6621808
    Abstract: A WCDMA system includes a Base Station (BS) or forward transmitter and a pilot channel that transmits control signals between a Mobile Station (MS) and BS to reconfigure their transmitter/receiver according to the prediction of the channel power and channel power probability density function separated into three distinct equal probable regions. Data signals are encoded using a one-half Viterbi encoder and interleaved. The interleaved data bits are modulated using Quadrature Phase Shift Keying (QPSK) modulation. The QPSK data is multiplexed with the pilot channel and spread by an appropriate code in an OFDM transmitter modified by a long code. Output of the transmitter may be provided to two diverse antennas for reliable communications to the receiver. Data may be received at two diverse antennas. The outputs are provided to match filters coupled to a coherent rake receiver and a channel prediction system.
    Type: Grant
    Filed: October 7, 1999
    Date of Patent: September 16, 2003
    Assignee: International Business Machines Corporation
    Inventor: Ali S. Sadri
  • Patent number: 6028890
    Abstract: A method and device for analog simultaneous voice and data transmission over an analog channel encodes at a voice signal sampling rate a sampled voice signal including spectral and pitch information. During encoding, the spectral and pitch information is extracted from the sampled voice signal to produce a residual signal, and the residual signal is converted into a sequence of residual vectors at a Baud rate. Then, a bitstream including non voice data and the extracted spectral and pitch information is produced. A modem unit, operating at Baud rate and producing an output carrier wave supplied to the analog channel, produces a sequence of symbol vectors in response to the sequence of residual vectors and the bitstream, and modulates the output carrier wave in response to the sequence of symbol vectors.
    Type: Grant
    Filed: June 4, 1997
    Date of Patent: February 22, 2000
    Assignees: International Business Machines Corporation, University de Sherbrooke
    Inventors: Redwan Salami, Claude Laflamme, Jean-Pierre Adoul, Ali S. Sadri, Sasan Ardalan, Hua Ye