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).
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Patent number: 8665742Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.Type: GrantFiled: September 15, 2011Date of Patent: March 4, 2014Assignee: Chanyu Holdings, LLCInventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
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Patent number: 8630269Abstract: A wireless network includes transmission power and data rate adaptation based upon quality experienced by the user.Type: GrantFiled: March 26, 2011Date of Patent: January 14, 2014Assignee: AT&T Intellectual Property II, L.P.Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Xiaoxin Qiu
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Publication number: 20120008559Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.Type: ApplicationFiled: September 15, 2011Publication date: January 12, 2012Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
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Patent number: 8037373Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.Type: GrantFiled: October 7, 2008Date of Patent: October 11, 2011Assignee: AT&T Intellectual Property II, L.P.Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
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Patent number: 7933251Abstract: A wireless network includes transmission power and data rate adaptation based upon quality experienced by the user.Type: GrantFiled: September 6, 2007Date of Patent: April 26, 2011Assignee: AT&T Intellectual Property II, L.P.Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Xiaoxin Qiu
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Publication number: 20090070641Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.Type: ApplicationFiled: October 7, 2008Publication date: March 12, 2009Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
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Patent number: 7457259Abstract: 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: GrantFiled: September 1, 2005Date of Patent: November 25, 2008Assignee: AT&T CorpInventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Bruce Edwin McNair, Xiaoxin Qiu
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Patent number: 7454512Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.Type: GrantFiled: September 1, 2006Date of Patent: November 18, 2008Assignee: AT&T Intellectual Property II, L.P.Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
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Patent number: 7280514Abstract: A wireless network includes transmission power and data rate adaptation based upon signal quality experienced by the user.Type: GrantFiled: August 12, 2005Date of Patent: October 9, 2007Assignee: AT&T Corp.Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Xiaoxin Qiu
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Patent number: 7124193Abstract: A method for improving the performance for a streaming service by link-adaptation and power-control in a wireless packet network such as an Enhanced General Packet Radio Services (EGPRS) cellular network is described. In particular, the effects of a combined link adaptation and power control scheme (referred to as an error-based scheme) for achieving a target error rate, which is non-zero but low enough so that limited retransmission and error concealment techniques are effective, is presented.Type: GrantFiled: August 23, 2001Date of Patent: October 17, 2006Assignee: AT&T Corp.Inventors: Kin K. Leung, Kapil K. Chawla, Peter F. Driessen, Xiaoxin Qiu
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Patent number: 7043254Abstract: Automated adjustment of system organization parameters in a wireless communication system is provided by determining the parameter settings using a characterization of signal propagation of the system's coverage area. This characterization is based on measurements of path loss-related characteristics by the system's base stations and wireless terminals. An exemplary path loss-related characteristic is path loss as determined by measuring received signal strength (RSS) at wireless terminals based on signals transmitted at known powers by a plurality of the system's base stations. It is possible for the wireless terminals to take measurement while operating in the coverage area, whether idle or during communication with the system, and for such terminals to be associated with the system's subscribers. A resulting characterization of signal propagation in the coverage area based on the measured path loss-related characteristic can then be used to determine a variety of parameter settings.Type: GrantFiled: February 25, 2002Date of Patent: May 9, 2006Assignee: Cingular Wireless II, LLCInventors: Kapil K. Chawla, Michael Jeffrey Dunn, Reinaldo A. Valenzuela
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Patent number: 6954465Abstract: 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: GrantFiled: February 22, 2001Date of Patent: October 11, 2005Assignee: AT&T Corp.Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Bruce Edwin McNair, Xiaoxin Qiu
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Patent number: 6950670Abstract: A wireless network includes transmission power and data rate adaptation based upon signal quality experienced by the user.Type: GrantFiled: October 31, 2001Date of Patent: September 27, 2005Assignee: AT&T Corp.Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Xiaoxin Qiu
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Patent number: 6754506Abstract: A TDMA wireless communication system adjusts the power control target and transmission power based upon link quality to enhance voice capacity. The power can be adjusted in response to the average SNIR and number of decoding errors in a link quality reporting period. The power control target can be increased and decreased in discrete intervals after evaluating the number of decoding errors in the reporting period. The transmission power can be adjusted towards the new power control target based upon the average SNIR.Type: GrantFiled: February 16, 2001Date of Patent: June 22, 2004Assignee: AT&T Wireless Services, Inc.Inventors: Li Fung Chang, Kapil K. Chawla, Justin Chi-I Chuang, Zoran Kostic, Xiaoxin Qiu, Nelson Ray Sollenberger, Shailender B. Timiri
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Publication number: 20030207695Abstract: A TDMA wireless communication system adjusts the power control target and transmission power based upon link quality to enhance voice capacity. The power can be adjusted in response to the average SNIR and number of decoding errors in a link quality reporting period. The power control target can be increased and decreased in discrete intervals after evaluating the number of decoding errors in the reporting period. The transmission power can be adjusted towards the new power control target based upon the average SNIR.Type: ApplicationFiled: February 16, 2001Publication date: November 6, 2003Inventors: Li Fung Chang, Kapil K. Chawla, Justin Chi-I Chuang, Zoran Kostic, Xiaoxin Qiu, Nelson Ray Sollenberger, Shailender B. Timiri
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Publication number: 20030083088Abstract: A wireless network includes transmission power and data rate adaptation based upon signal quality experienced by the user.Type: ApplicationFiled: October 31, 2001Publication date: May 1, 2003Inventors: Li Fung Chang, Kapil K. Chawla, Justin Che-I Chuang, Xiaoxin Qiu
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Patent number: 6532225Abstract: An arrangement where, in addition to the control channels that are used to set up sessions, there is a logically and physically separate and independent set of control channels that can be used as session control channels. Illustratively, the physical GSM frame arrangement that employs 8 logical slots is used, with one slot both in the uplink and downlink dedicated to these separate control channels. In the downlink, such a control channel provides channel grant information, requests to make and transmit power measurements, poll mobile units, etc. In the uplink, such a control channel can be used to request access to a traffic channel, to report on power measurements, to request special hand-off handling, to respond to polling, etc. Because the uplink session control channel does not need to carry a significant amount of information, the GSM slot can be divided into minislots, with each minislot constituting a session control channel for a group of mobile units.Type: GrantFiled: July 27, 1999Date of Patent: March 11, 2003Assignee: AT&T CorpInventors: Li Fung Chang, Kapil K. Chawla, Justin C. Chuang, Xiaoxin Qiu, Nelson R. Sollenberger
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Patent number: 6501785Abstract: This invention provides a dynamic frequency hopping system that utilizes information from multiple base stations. The system assigns frequency hopping patterns based on current interference and traffic environments to avoid interference thus gaining the benefits of interference averaging and interference avoidance. The system imposes less stringent measurement requirements on terminals (wireless mobile devices) because many measurement requirements are replaced by generating estimates based on measurement data received from other base stations within a base station neighborhood. The system may continuously verify that the frequency hopping patterns assigned to the links of the system optimizes system performance. The system compares system performance of possible frequency hopping patterns against currently assigned frequency hopping pattern to optimize system performance.Type: GrantFiled: December 28, 1999Date of Patent: December 31, 2002Assignee: AT&T Corp.Inventors: Li Fung Chang, Kapil K. Chawla, Justin C. Chuang, Zoran Kostic, Nelson Sollenberger, Xiaoxin Qiu
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Patent number: 6496700Abstract: A level of automated adjustment of system organization parameters in a wireless communication system is provided by determining the parameter settings using a characterization of signal propagation of the system's coverage area. This characterization is based on measurements of path loss-related characteristics by the system's base stations and wireless terminals operating throughout the coverage area. An exemplary path loss-related characteristic is path loss as determined by measuring received signal strength (RSS) at wireless terminals based on signals transmitted at known powers by a plurality of the system's base stations. It is possible for the wireless terminals to take measurements while operating in the coverage area, whether idle or during communication with the system, and for such terminals to be associated with the system's subscribers.Type: GrantFiled: April 4, 1996Date of Patent: December 17, 2002Assignee: AT&T Wireless Services, Inc.Inventors: Kapil K. Chawla, Michael Jeffrey Dunn, Reinaldo A. Valenzuela
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Publication number: 20020142788Abstract: A level of automated adjustment of system organization parameters in a wireless communication system is provided by determining the parameter settings using a characterization of signal propagation of the system's coverage area. This characterization is based on measurements of path loss-related characteristics by the system's base stations and wireless terminals operating throughout the coverage area. An exemplary path loss-related characteristic is path loss as determined by measuring received signal strength (RSS) at wireless terminals based on signals transmitted at known powers by a plurality of the system's base stations. It is possible for the wireless terminals to take measurements while operating in the coverage area, whether idle or during communication with the system, and for such terminals to be associated with the system's subscribers.Type: ApplicationFiled: February 25, 2002Publication date: October 3, 2002Applicant: AT&T Wireless Services, Inc.Inventors: Kapil K. Chawla, Michael Jeffrey Dunn, Reinaldo A. Valenzuela