Patents by Inventor Shirish Nagaraj

Shirish Nagaraj 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).

  • Patent number: 8260340
    Abstract: Methods of reverse link power control are provided. A first example method includes first measuring a first type of interference, second measuring a second type of interference, determining a ratio between the first and second measurements and broadcasting the determined ratio to a plurality of mobile units. A second example method includes receiving a broadcasted ratio indicating a ratio between two different types of interference and calculating a power level for reverse link transmissions based on the received broadcasted ratio. A third example method includes first adjusting OFDMA transmission power based on first feedback signals during an OFDMA transmission and second adjusting OFDMA transmission power based on second feedback signals during periods between OFDMA transmissions.
    Type: Grant
    Filed: February 17, 2006
    Date of Patent: September 4, 2012
    Assignee: Alcatel Lucent
    Inventors: Suman Das, Shirish Nagaraj, Harish Viswanathan
  • Patent number: 8189453
    Abstract: Improvements are provided in an OFDM network that uses superposition coding. A broadcast signal and e.g. a unicast signal are each subjected to OFDM modulation including processing by an IDFT, combined, and transmitted using non-orthogonal transmission resources. In one approach, the respective signals are combined after instead of before the IDFT processing. In specific examples, a respective cyclic prefix is appended to each signal after the IDFT processing but before the respective signals are combined. In another approach, a broadcast pilot signal and e.g. a unicast pilot signal are transmitted concurrently with the broadcast and unicast information signals. The pilot signals are transmitted using the same time and subcarrier resources, but are made more distinguishable by combining each with a respective scrambling or spreading code. In specific examples, embodiments, the unicast pilot signal is used for estimating the data rate for transmission of further unicast information signals.
    Type: Grant
    Filed: March 6, 2009
    Date of Patent: May 29, 2012
    Assignee: Alcatel Lucent
    Inventors: Pantelis Monogioudis, Shirish Nagaraj, Sivarama Krishnan Venkatesan, Harish Viswanathan
  • Patent number: 8125935
    Abstract: Whether to process a control channel corresponding to a data channel carrying transmitted data based on a re-transmission indicator and a threshold value is determined at the receiver. The re-transmission indicator indicates a number of times the transmitted data has been transmitted. Control information received on the control channel is then selectively processed based on the determining step.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: February 28, 2012
    Assignee: Alcatel Lucent
    Inventors: Francis Dominique, Shirish Nagaraj, Hongwei Kong, Walid Elias Nabhane
  • Patent number: 7986627
    Abstract: A signaling method is provided that can improve the efficiency of forward-link control signaling in OFDM systems. The method involves using a set of forward-link subcarriers that are dedicated for control information, and are shared by a set of two or more users. The control information destined for each user is spread using a respective spreading code, thereby to provide a spread control message. The spread control messages destined for the various users are summed together prior to transmission.
    Type: Grant
    Filed: January 13, 2006
    Date of Patent: July 26, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Suman Das, Shirish Nagaraj, Subramanian Vasudevan, Harish Viswanathan
  • Patent number: 7920469
    Abstract: A method and an apparatus for wireless communication between a receiver and a transmitter in a cellular system are provided. The method comprises associating a channel of known structure at the transmitter with the transmission of a first control channel to indicate a variable structure of the first control channel to the receiver.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: April 5, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Shupeng Li, Shirish Nagaraj, Sudhir Ramakrishna, Ashok N. Rudrapatna
  • Patent number: 7864683
    Abstract: A method is provided for communicating data belonging to at least one application flow (AF). In one aspect, the method involves mapping the data to payload bits of two or more encoder packets (EPs) such that each said EP carries a payload dedicated to only one AF, and transmitting the EPs concurrently. In a second aspect, the above said mapping is inverted at a receiver.
    Type: Grant
    Filed: August 15, 2008
    Date of Patent: January 4, 2011
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Shupeng Li, Shirish Nagaraj, Sudhir Ramakrishna, Ashok N. Rudrapatna
  • Patent number: 7734308
    Abstract: Whether a receiver supports blind data channel detection is determined, and transmission of control channel information associated with a data channel is disabled if the determining step determines the receiver is capable of detecting the data channel without the use of control channel information. Data is transmitted to the receiver on the data channel without the control channel information after disabling of the transmission of the control channel information.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: June 8, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Francis Dominique, Shirish Nagaraj, Hongwei Kong, Walid Elias Nabhane
  • Patent number: 7693099
    Abstract: In a method of wireless communication, signaling information in a received signal may be detected using a detection parameter. The detection parameter may be determined based on at least one of a probability of false alarm and a target probability of false alarm. Another method may detect signaling information using an estimated transmission probability value for a subsequent time instant that is determined based on an estimated transmission probability value for a current time instant. The detection parameter may also be determined from the estimated probability of transmission values.
    Type: Grant
    Filed: May 26, 2004
    Date of Patent: April 6, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Sridhar Gollamudi, Shirish Nagaraj
  • Patent number: 7684512
    Abstract: In an example method of scheduling mobile users, mobile users are assigned to one of at least a first layer and a second layer, where each of the first and second layers are associated with a same frequency band. The mobile users are further assigned, in the first layer, to different frequency sub-bands in the frequency band such that the users in the first layer have non-overlapping first sub-band assignments. The mobile users are further assigned, in the second layer, to different frequency sub-bands in the frequency band such that the users in the second layer have non-overlapping second sub-band assignments. The mobile users are then scheduled for transmission based on the first and second layer and the first and second sub-band assignments. In a further example decoding method, layer transmissions are decoded in succession with interference cancellation performed between each layer decoding step.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: March 23, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventor: Shirish Nagaraj
  • Publication number: 20100040157
    Abstract: A method is provided for communicating data belonging to at least one application flow (AF). In one aspect, the method involves mapping the data to payload bits of two or more encoder packets (EPs) such that each said EP carries a payload dedicated to only one AF, and transmitting the EPs concurrently. In a second aspect, the above said mapping is inverted at a receiver.
    Type: Application
    Filed: August 15, 2008
    Publication date: February 18, 2010
    Inventors: Shupeng Li, Shirish Nagaraj, Sudhir Ramakrishna, Ashok N. Rudrapatna
  • Patent number: 7643438
    Abstract: In a method for determining link level performance of random access channel (RACH) preamble detection in a wireless communication system, link level performance results may be obtained without having to perform extensive simulation. Link-level performance results of RACH preamble detection may be characterized by determining a conditional detection probability. The conditional detection probability may be conditioned upon an instantaneous channel coefficient, and the conditional detection probability may be expressed in terms of an instantaneous detection metric. Instantaneous link-level performance may be characterized using a look-up table, so that a system model evaluated in accordance with the method may accurately represent instantaneous system behavior.
    Type: Grant
    Filed: August 28, 2003
    Date of Patent: January 5, 2010
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Jung Ah Lee, Shirish Nagaraj
  • Publication number: 20090279478
    Abstract: Various embodiments are described for potentially improving coverage and/or the cell-edge outage rate and thereby the system capacity. Logic flow diagrams 10 and 20, in FIGS. 1 and 2, depict functionality performed by communication devices in the system. A first communication device, attempting to successfully receive (12) signaling from a source communication device, transmits (14) signaling indicating that it is requesting an interfering communication device to reduce transmissions that may be interfering with signaling from the source communication device. In response to this signaling from the first communication device (22), the interfering communication device reduces (24) transmissions based at least in part on what was indicated by the signaling from the first communication device. Thus, cooperative interference reduction may be achieved dynamically by receiving devices signaling other devices in the system to request interference relief when needed.
    Type: Application
    Filed: May 23, 2008
    Publication date: November 12, 2009
    Applicant: MOTOROLA, INC.
    Inventors: Shirish Nagaraj, Philip J. Fleming
  • Publication number: 20090175162
    Abstract: Improvements are provided in an OFDM network that uses superposition coding. A broadcast signal and e.g. a unicast signal are each subjected to OFDM modulation including processing by an IDFT, combined, and transmitted using non-orthogonal transmission resources. In one approach, the respective signals are combined after instead of before the IDFT processing. In specific examples, a respective cyclic prefix is appended to each signal after the IDFT processing but before the respective signals are combined. In another approach, a broadcast pilot signal and e.g. a unicast pilot signal are transmitted concurrently with the broadcast and unicast information signals. The pilot signals are transmitted using the same time and subcarrier resources, but are mad e more distinguishable by combining each with a respective scrambling or spreading code. In specific examples, embodiments, the unicast pilot signal is used for estimating the data rate for transmission of further unicast information signals.
    Type: Application
    Filed: March 6, 2009
    Publication date: July 9, 2009
    Inventors: Pantelis Monogioudis, Shirish Nagaraj, Sivarama Krishnan Venkatesan, Harish Viswanathan
  • Patent number: 7558191
    Abstract: Improvements are provided in an OFDM network that uses superposition coding. A broadcast signal and e.g. a unicast signal are each subjected to OFDM modulation including processing by an IDFT, combined, and transmitted using non-orthogonal transmission resources. In one approach, the respective signals are combined after instead of before the IDFT processing. In specific examples, a respective cyclic prefix is appended to each signal after the IDFT processing but before the respective signals are combined. In another approach, a broadcast pilot signal and e.g. a unicast pilot signal are transmitted concurrently with the broadcast and unicast information signals. The pilot signals are transmitted using the same time and subcarrier resources, but are made more distinguishable by combining each with a respective scrambling or spreading code. In specific examples, embodiments, the unicast pilot signal is used for estimating the data rate for transmission of further unicast information signals.
    Type: Grant
    Filed: September 7, 2006
    Date of Patent: July 7, 2009
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Pantelis Monogioudis, Shirish Nagaraj, Sivarama Krishnan Venkatesan, Harish Viswanathan
  • Patent number: 7515927
    Abstract: A closed loop power control based on receiving a continuous quality feedback is described. A main reverse link (RL) pilot is controlled by the quality feedback of a substantially continuous delay sensitive traffic stream, such as Voice-over-IP (VoIP), when such a stream is enabled. When such a stream is not enabled, the quality of a continuous RL overhead channel is used to control the pilot power. At the same time, the Traffic-to-Pilot Ratios (TPR) of contemporaneously transmitted delay sensitive data streams are independently adjusted based on a quality feedback associated with each such data stream.
    Type: Grant
    Filed: January 13, 2006
    Date of Patent: April 7, 2009
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Suman Das, Pantelis Monogioudis, Shirish Nagaraj, Subramanian Vasudevan, Harish Viswanathan, Jialin Zou
  • Patent number: 7486954
    Abstract: In the method, rate control for at least one soft handoff user is selectively performed based on a soft handoff loading metric indicative of loading from soft handoff users on the channel.
    Type: Grant
    Filed: March 25, 2005
    Date of Patent: February 3, 2009
    Assignee: Alcatel-Lucent USA Inc.
    Inventors: Jung Ah Lee, Shirish Nagaraj, Anil M. Rao
  • Patent number: 7453821
    Abstract: In a method of detecting signaling information in a signal received in a wireless communication system, signaling information for a signal received in a subsequent time instant may be detected using an estimated value for the subsequent time instant. The estimated value for the subsequent time instant may be determined based on one or more measured parameters related to an estimated value for detecting signaling information in a current time instant.
    Type: Grant
    Filed: May 26, 2004
    Date of Patent: November 18, 2008
    Assignee: Lucent Technologies Inc.
    Inventor: Shirish Nagaraj
  • Publication number: 20080160951
    Abstract: Whether to process a control channel corresponding to a data channel carrying transmitted data based on a re-transmission indicator and a threshold value is determined at the receiver. The re-transmission indicator indicates a number of times the transmitted data has been transmitted. Control information received on the control channel is then selectively processed based on the determining step.
    Type: Application
    Filed: December 27, 2006
    Publication date: July 3, 2008
    Inventors: Francis Dominique, Shirish Nagaraj, Hongwei Kong, Walid Elias Nabhane
  • Publication number: 20080159237
    Abstract: Whether a receiver supports blind data channel detection is determined, and transmission of control channel information associated with a data channel is disabled if the determining step determines the receiver is capable of detecting the data channel without the use of control channel information. Data is transmitted to the receiver on the data channel without the control channel information after disabling of the transmission of the control channel information.
    Type: Application
    Filed: December 27, 2006
    Publication date: July 3, 2008
    Inventors: Francis Dominique, Shirish Nagaraj, Hongwei Kong, Walid Elias Nabhane
  • Patent number: 7352825
    Abstract: The disclosed embodiments relate to a communication system and method. The system may comprise a pre-whitening device that applies pre-whitening data to a received signal from an antenna array to produce a pre-whitened signal, at least one detector that is adapted to recognize a pattern corresponding to a request for access in the pre-whitened signal and compute correlation data corresponding to the pattern, and a threshold detector that determines whether the correlation data exceeds a threshold and indicates that an acknowledgement signal should be transmitted if the threshold is exceeded. The method may comprise the acts of creating a pre-whitened signal by applying pre-whitening data to a received signal, detecting a pattern that corresponds to a request for access in the pre-whitened signal, computing correlation data corresponding to the pattern, determining whether the correlation data exceeds a threshold, and indicating that an acknowledgement signal should be transmitted if the threshold is exceeded.
    Type: Grant
    Filed: December 1, 2003
    Date of Patent: April 1, 2008
    Assignee: Lucent Technologies Inc.
    Inventors: Deepak Das, Jung Ah Lee, Shirish Nagaraj, Anil M. Rao