Patents by Inventor Peroor K. Sebastian

Peroor K. Sebastian 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: 20030003920
    Abstract: Adapting a wireless communications link between a transmitter and a receiver involves reducing the RF bandwidth of an uplink communications channel to achieve a desired channel quality. The RF bandwidth of the uplink communications channel is reduced when the desired channel quality is not achieved using the entire available RF bandwidth for uplink communications. Reducing the RF bandwidth of an uplink channel enables the uplink limit of a subscriber unit to be extended beyond what is possible when the entire available RF bandwidth is used for uplink communications. Additional uplink time slots can be allocated to the uplink communications channel with the reduced RF band so that a constant overall transmission rate can be maintained between the transmitter and the receiver.
    Type: Application
    Filed: June 28, 2001
    Publication date: January 2, 2003
    Inventor: Peroor K. Sebastian
  • Publication number: 20020136287
    Abstract: A first embodiment of the present invention is a method for displaying the quality of a wireless data transmission. The method involves receiving the wireless data transmission wherein the wireless data transmission comprises multiple streams of data, determining the quality of the wireless data transmission based on a quality parameter of the wireless data transmission and displaying the quality of the wireless data transmission. A second embodiment of the present invention includes an apparatus for indicating the quality of a wireless data transmission. The apparatus includes means for receiving the wireless data transmission wherein the wireless data transmission comprises multiple streams of data, means for determining the quality of the wireless data transmission based on a quality parameter of the wireless data transmission and means for displaying the quality of the wireless data transmission. A third embodiment of the present invention includes a wireless communication system.
    Type: Application
    Filed: March 20, 2001
    Publication date: September 26, 2002
    Inventors: Robert W. Heath, Peroor K. Sebastian
  • Patent number: 6442214
    Abstract: The present invention provides a diversity transmission system. The diversity transmission system includes a diversity transmitter receiving incoming symbols. The diversity transmitter includes at least one transmitter antenna transmitting a plurality of multi-carrier modulated signals. Each multi-carrier-modulated signal includes a corresponding processed symbol sub-block stream. Each symbol of the processed symbol sub-block stream is based on a linear transform of a plurality of incoming symbols. The diversity transmission system further includes a diversity receiver. The diversity receiver includes at least one receiver antenna receiving the plurality of multi-carrier modulated signals after the multi-carrier modulated signals having been modified by transmission channels between the transmitter antennas and the receiver antenna.
    Type: Grant
    Filed: May 19, 2000
    Date of Patent: August 27, 2002
    Assignee: Iospan Wireless, Inc.
    Inventors: Helmut Boleskei, Peroor K. Sebastian, Shilpa Talwar, Arogyaswami J. Paulraj
  • Patent number: 6400699
    Abstract: The invention includes an apparatus and method for scheduling wireless transmission of data blocks between at least one antenna of a base transceiver station and multiple subscriber units. The scheduling can be based on the quality of a transmission link between the base station antennas and the subscriber units, the amount of data requested by the subscriber units, and/or the type of data requested by the subscriber units. The scheduling generally includes assigning frequency blocks and time slots to each of the subscriber units for receiving or transmitting data blocks. The invention includes a method for transmitting data streams between a base transceiver station and a plurality of subscribers.
    Type: Grant
    Filed: September 12, 2000
    Date of Patent: June 4, 2002
    Assignee: Iospan Wireless, Inc.
    Inventors: Manish Airy, Baraa Al-Dabagh, Jose Tellado, Partho Mishra, John Fan, Peroor K. Sebastian, Arogyaswami J. Paulraj
  • Patent number: 6377819
    Abstract: A wireless communication system comprises a base transceiver station and R remote transceivers T1 . . . TR, each of the remote transceivers having multiple antennas. The base transceiver station has N base station antennas, each of the remote transceivers has M remote antennas, and N≧R. The base transceiver station simultaneously transmits information signals s1 . . . sR to remote transceivers T1 . . . TR, respectively. The base transceiver station comprises processing means for selecting R discrimination vectors V1 . . . VR, each of the discrimination vectors having N components. The base transceiver station computes an N-component transmission signal vector U as follows: U = ∑ i = 1 R ⁢   ⁢ V i ⁢ s i .
    Type: Grant
    Filed: April 6, 2000
    Date of Patent: April 23, 2002
    Assignee: Iospan Wireless, Inc.
    Inventors: David J. Gesbert, Peroor K. Sebastian, Arogyaswami J. Paulraj
  • Patent number: 6377632
    Abstract: A method and apparatus for wireless transmission of a digital bit stream. The present method employs diversity techniques to minimize multipath fading. Digital bits are converted into symbols and the symbols are provided to a number of diversity branches. Each diversity branch has its own antenna. The symbols sent to each diversity branch may be multiplied by a different phase factor or amplitude factor. The phase factors and amplitude factors may be randomly selected. Also, wireless channels can be monitored for channel quality. In this case, the channel quality measurements are used to select the phase factors and the amplitude factors. Also, the symbols can be grouped into frames before transmission. In this case, the frames can be multiplied by matrices comprising phase factors and amplitude factors. Also in this case, the frames can undergo cyclic shifting, which provides an additional measure of diversity.
    Type: Grant
    Filed: January 24, 2000
    Date of Patent: April 23, 2002
    Assignee: Iospan Wireless, Inc.
    Inventors: Arogyaswami J. Paulraj, Peroor K. Sebastian, Jose Tellado, Robert W. Heath, Jr., Shilpa Talwar, Helmut Bölcskei
  • Patent number: 6377636
    Abstract: A method for interference mitigation in a wireless communication system having multiple transmitters and receivers by introducing transmission time delays between the transmission of signals from the individual transmitters to ensure coherent reception of the signals at a specific point in the coverage area, such as at a center of distribution of the receivers. To further aid in interference mitigation the signals are assigned training patterns chosen to be distinguishable by the receiver and to optimize interference mitigation. The training patterns can be selected based on a feedback parameter, e.g., a measure of the quality of interference mitigation obtained from the receiver. The present method can be used in wireless communication systems which re-use frequencies including TDMA, CDMA, FDMA, OFDMA or other multiplex communication systems using a multiple access method or a combination of such methods.
    Type: Grant
    Filed: November 2, 1999
    Date of Patent: April 23, 2002
    Assignee: Iospan Wirless, Inc.
    Inventors: Arogyaswami J. Paulraj, Peroor K. Sebastian, Jose Tellado, Robert W. Heath, Jr.
  • Publication number: 20020027957
    Abstract: A method for interference mitigation in a wireless communication system having multiple transmitters and receivers by introducing transmission time delays between the transmission of signals from the individual transmitters to ensure coherent reception of the signals at a specific point in the coverage area, such as at a center of distribution of the receivers. To further aid in interference mitigation the signals are assigned training patterns chosen to be distinguishable by the receiver and to optimize interference mitigation. The training patterns can be selected based on a feedback parameter, e.g., a measure of the quality of interference mitigation obtained from the receiver. The present method can be used in wireless communication systems which re-use frequencies including TDMA, CDMA, FDMA, OFDMA or other multiplex communication systems using a multiple access method or a combination of such methods.
    Type: Application
    Filed: June 6, 2001
    Publication date: March 7, 2002
    Inventors: Arogyaswami J. Paulraj, Peroor K. Sebastian, Jose Tellado, Robert W. Heath
  • Patent number: 6351499
    Abstract: A method of maximizing a communication parameter, such as data capacity, signal quality or throughput of a channel between a transmit unit with M transmit antennas and a receive unit with N receive antennas and a communication system such as a wireless network (including networks with multiple access techniques such as TDMA, FDMA, CDMA, OFDMA) employing the method. The data is first processed to produce parallel spatial-multiplexed streams SMi, where i=1 . . . k, which are converted or mapped to transmit signals TSp, where p=1 . . . M, assigned for transmission from the M transmit antennas. Corresponding receive signals RSj, where j=1 . . . N, are received by the N receive antennas of the receiver and used to assess a quality parameter, such as a statistical signal parameter including SINR, SNR, power level, level crossing rate, level crossing duration of the signal of a predetermined threshold and reception threshold, or a parameter of the data, such as BER or packet error rate.
    Type: Grant
    Filed: December 15, 1999
    Date of Patent: February 26, 2002
    Assignee: Iospan Wireless, Inc.
    Inventors: Arogyaswami J. Paulraj, Peroor K. Sebastian, David J. Gesbert, Jose Tellado
  • Patent number: 6298092
    Abstract: The present invention provides a method for controlling a communication parameter in a channel through which data is transmitted between a transmit unit with M transmit antennas and a receive unit with N receive antennas by selecting from among proposed mapping schemes an applied mapping scheme according to which the data is converted into symbols and assigned to transmit signals TSp, p=1 . . . M, which are transmitted from the M transmit antennas. The selection of the mapping scheme is based on a metric; in one embodiment the metric is a minimum Euclidean distance dmin,rx of the symbols when received, in another embodiment the metric is a probability of error P(e) in the symbol when received. The method can be employed in communication systems using multi-antenna transmit and receive units of various types including wireless systems, e.g., cellular communication systems, using multiple access techniques such as TDMA, FDMA, CDMA and OFDMA.
    Type: Grant
    Filed: June 2, 2000
    Date of Patent: October 2, 2001
    Assignee: Iospan Wireless, Inc.
    Inventors: Robert W. Heath, Jr., Peroor K. Sebastian, Arogyaswami J. Paulraj
  • Patent number: 6067290
    Abstract: The present invention provides methods and apparatus for implementing spatial multiplexing in conjunction with the one or more multiple access protocols during the broadcast of information in a wireless network. A wireless cellular network for transmitting subscriber datastream(s) to corresponding ones among a plurality of subscriber units located within the cellular network is disclosed. The wireless cellular network includes base stations and a logic. The base stations each include spatially separate transmitters for transmitting, in response to control signals, selected substreams of each subscriber datastream on an assigned channel of a multiple access protocol. The logic communicates with each of the base stations. The logic assigns an available channel on which to transmit each subscriber datastream. The logic routes at least a substream of each datastream to at least a selected one of the base stations.
    Type: Grant
    Filed: July 30, 1999
    Date of Patent: May 23, 2000
    Assignee: Gigabit Wireless, Inc.
    Inventors: Arogyaswami J. Paulraj, Robert W. Heath, Jr., Peroor K. Sebastian, David J. Gesbert