Patents by Inventor Kapil K. Chawla

Kapil K. Chawla 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: 6459901
    Abstract: This invention provides wireless resource allocation techniques where the wireless network resource allocation is based on maximum system gain. System gain may be the difference between a maximum performance (e.g., throughput rate) for a requested link and a performance loss of all currently active links affected by the requested link. A currently active link is affected if the requested link is within its link neighborhood. Wireless network resources are allocated to optimize system performance. Inter-base communication may be used to facilitate information exchange among base stations to optimize system performance. The performance loss experienced by any currently active link is called damage to that link. Damage may be determined in a pair-wise fashion based on a nominal performance which may be defined as the performance of a link if interference is experienced only from links which are outside the link neighborhood of the link or as a system parameter.
    Type: Grant
    Filed: December 3, 1999
    Date of Patent: October 1, 2002
    Assignee: AT&T Corp.
    Inventors: Kapil K. Chawla, Justin Che-I Chuang, Xiaoxin Qiu, Nelson Ray Sollenberger
  • Publication number: 20010048691
    Abstract: This invention provides interference predictions, suitable for least interference dynamic channel assignment use or other frequency hopping uses by de-coupling the time slot assignment and the frequency hopping pattern assignment. In particular, a least interfered time slot is selected based on an aggregate interference measurement performed across an entire transmission band or a pre-specified range of frequencies in the transmission band. A user is assigned a least interfered time slot and provided an appropriate frequency hopping pattern.
    Type: Application
    Filed: February 22, 2001
    Publication date: December 6, 2001
    Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Bruce Edwin McNair, Xiaoxin Qiu
  • Patent number: 6243371
    Abstract: A method and apparatus for managing interference in a wireless communications system. Each base generates a predictable beam-off sequence, and terminals measure the received signal over time. This received signal is then used to estimate or measure performance to schedule transmissions to the terminal.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: June 5, 2001
    Assignee: AT&T Corp.
    Inventors: Kapil K. Chawla, Xiaoxin Qiu
  • Patent number: 6137787
    Abstract: A method and apparatus for assigning communication resources for at least one communication site in a time division communication system having multiple reuse patterns in the time domain. A first plurality of communication sites communicate using a first portion of a time frame corresponding to a first reuse pattern. A second plurality of communication sites communicate using a second portion of said time frame corresponding to a second reuse pattern.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: October 24, 2000
    Inventors: Kapil K. Chawla, Xiaoxin Qiu
  • Patent number: 5878328
    Abstract: A level of system self-organization in a wireless communication system is provided using a combined design, planning and verification process to determine system organization parameters. The process determines the parameters based on a measured path loss-related characteristic, such as path loss or bit error rate, between base stations and a plurality of regions in a coverage area. For each region, the characteristic is measured to each base station irrespective of the proximity between the region and the base stations. The measured characteristics enable the prediction of signal strength received at the regions of signals transmitted by the base stations independent of the region location. Accordingly, the characteristics can be measured without information correlating the absolute geographic locations of the regions.
    Type: Grant
    Filed: December 21, 1995
    Date of Patent: March 2, 1999
    Assignee: AT&T Wireless Services, Inc.
    Inventors: Kapil K. Chawla, Michael Jeffrey Dunn, Masud Kibria, Michael Allen Raffel, Reinaldo A. Valenzuela