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Prathima Agrawal

Other affiliations: Rutgers University, AT&T Labs, Bell Labs  ...read more
Bio: Prathima Agrawal is an academic researcher from Auburn University. The author has contributed to research in topics: Wireless network & Network packet. The author has an hindex of 54, co-authored 309 publications receiving 11032 citations. Previous affiliations of Prathima Agrawal include Rutgers University & AT&T Labs.


Papers
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Journal ArticleDOI
TL;DR: A comprehensive summary of recent work addressing energy efficient and low-power design within all layers of the wireless network protocol stack of wireless networks is presented.
Abstract: Wireless networking has witnessed an explosion of interest from consumers in recent years for its applications in mobile and personal communications. As wireless networks become an integral component of the modern communication infrastructure, energy efficiency will be an important design consideration due to the limited battery life of mobile terminals. Power conservation techniques are commonly used in the hardware design of such systems. Since the network interface is a significant consumer of power, considerable research has been devoted to low-power design of the entire network protocol stack of wireless networks in an effort to enhance energy efficiency. This paper presents a comprehensive summary of recent work addressing energy efficient and low-power design within all layers of the wireless network protocol stack.

958 citations

Journal ArticleDOI
10 Dec 2002
TL;DR: In this paper, a fuzzy logic controlled, three-phase shunt active power filter is proposed to improve power quality by compensating harmonics and reactive power required by a nonlinear load.
Abstract: The simulation and experimental study of a fuzzy logic controlled, three-phase shunt active power filter to improve power quality by compensating harmonics and reactive power required by a nonlinear load is presented. The advantage of fuzzy control is that it is based on a linguistic description and does not require a mathematical model of the system. The fuzzy control scheme is realised on an inexpensive dedicated micro-controller (INTEL 8031) based system. The compensation process is based on sensing line currents only, an approach different from conventional methods, which require harmonics or reactive volt-ampere requirement of the load. The performance of the fuzzy logic controller is compared with a conventional PI controller. The dynamic behavior of the fuzzy controller is found to be better than the conventional PI controller. PWM pattern generation is based on carrierless hysteresis based current control to obtain the switching signals. Various simulation and experimental results are presented under steady state and transient conditions.

327 citations

Patent
25 Jul 1997
TL;DR: In this article, a method adapts scheduling priorities in a CDMA wireless communications system to conserve battery power in mobile terminals operating within the system, based on the battery power level information and other setup information, the base station adjusts scheduling priorities for the mobile terminals to expedite wireless transmissions from those mobile terminals reporting low battery power levels.
Abstract: A method adapts scheduling priorities in a CDMA wireless communications system to conserve battery power in mobile terminals operating within the system. A base station, within the system, receives battery power level information and other setup information from mobile terminals operating within the service area of the base station during call setup procedures. Based on the battery power level information and other setup information, the base station adapts scheduling priorities for the mobile terminals to expedite wireless transmissions from those mobile terminals reporting low battery power levels. The base station schedules the transmissions from low battery power mobile stations to be clustered together in a low-power time slot which is separate in time from the scheduled transmissions from high battery power mobile stations. The base station transmits a power control message to the low battery power mobile stations, to reduce the transmission power required for those mobile stations during the low-power time slot.

303 citations

Proceedings ArticleDOI
25 Oct 1998
TL;DR: The paper introduces the concept of a long-term fairness server to efficiently keep track of the amount of supplemental bandwidth for each session, and allows one to easily integrate the proposed approach with any of the existing PFQ algorithms.
Abstract: Parames~varan Ramana.tllan Pratbinla t\graIval Dept. of Elect. & Comp. Engr. I[)ter]~et. ArcIl. Research Lab University of Wisconsin Bellcore, hIorristotvn Nladison, WI 53706 Ne\v .Jersey 07960. parmesll!@ece.\visc.edu pagra~val(~bellcore. com Bit errors are fairly common during transmission in a wireless network. As a result, a straight-forwarcl application of existing packet fair queueing (PFQ) algorithms from wireIine to wireless networks results in an ine~cient use of ~he Kmited wireless bandwidth. In this paper, we propose a simple approach for adapting the existing PFQ algorithms for the wire]ine networks to provide the same kind of long-term fairness guarantees while making efficient use of the wireless bandwidth. In the proposed approach, long-term fairness guarantees are provided by supplementing the bandwidth given to sessions which have not received satisfactory service in the short -term due to poor quahty of their wireless channel. To efficiently keep track of the amount of supplemental bandwidth for each session, the paper introduces the concept of a long-term fairness server. This concept. also allows one to easily integrate the proposed approach with any of the existing PFQ algorithms.

266 citations

Proceedings ArticleDOI
19 Jun 2006
TL;DR: This paper proposes a novel and automated location determination method called ARIADNE, using a two dimensional construction floor plan and only a single actual signal strength measurement, which generates an estimated signal strength map comparable to those generated manually by actual measurements.
Abstract: Location determination of mobile users within a building has attracted much attention lately due to its many applications in mobile networking including network intrusion detection problems. However, it is challenging due to the complexities of the indoor radio propagation characteristics exacerbated by the mobility of the user. A common practice is to mechanically generate a table showing the radio signal strength at different known locations in the building. A mobile user's location at an arbitrary point in the building is determined by measuring the signal strength at the location in question and determining the location by referring to the above table using a LMSE (least mean square error) criterion. Obviously, this is a very tedious and time consuming task. This paper proposes a novel and automated location determination method called ARIADNE. Using a two dimensional construction floor plan and only a single actual signal strength measurement, ARIADNE generates an estimated signal strength map comparable to those generated manually by actual measurements. Given the signal measurements for a mobile, a proposed clustering algorithm searches that signal strength map to determine the current mobile's location. The results from ARIADNE are comparable and may even be superior to those from existing localization schemes.

259 citations


Cited by
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Journal ArticleDOI
TL;DR: The concept of sensor networks which has been made viable by the convergence of micro-electro-mechanical systems technology, wireless communications and digital electronics is described.

17,936 citations

Journal ArticleDOI
TL;DR: This work develops and analyzes low-energy adaptive clustering hierarchy (LEACH), a protocol architecture for microsensor networks that combines the ideas of energy-efficient cluster-based routing and media access together with application-specific data aggregation to achieve good performance in terms of system lifetime, latency, and application-perceived quality.
Abstract: Networking together hundreds or thousands of cheap microsensor nodes allows users to accurately monitor a remote environment by intelligently combining the data from the individual nodes. These networks require robust wireless communication protocols that are energy efficient and provide low latency. We develop and analyze low-energy adaptive clustering hierarchy (LEACH), a protocol architecture for microsensor networks that combines the ideas of energy-efficient cluster-based routing and media access together with application-specific data aggregation to achieve good performance in terms of system lifetime, latency, and application-perceived quality. LEACH includes a new, distributed cluster formation technique that enables self-organization of large numbers of nodes, algorithms for adapting clusters and rotating cluster head positions to evenly distribute the energy load among all the nodes, and techniques to enable distributed signal processing to save communication resources. Our results show that LEACH can improve system lifetime by an order of magnitude compared with general-purpose multihop approaches.

10,296 citations

Book
01 Jan 2005

9,038 citations

Proceedings Article
01 Jan 2005
TL;DR: This book aims to provide a chronology of key events and individuals involved in the development of microelectronics technology over the past 50 years and some of the individuals involved have been identified and named.
Abstract: Alhussein Abouzeid Rensselaer Polytechnic Institute Raviraj Adve University of Toronto Dharma Agrawal University of Cincinnati Walid Ahmed Tyco M/A-COM Sonia Aissa University of Quebec, INRSEMT Huseyin Arslan University of South Florida Nallanathan Arumugam National University of Singapore Saewoong Bahk Seoul National University Claus Bauer Dolby Laboratories Brahim Bensaou Hong Kong University of Science and Technology Rick Blum Lehigh University Michael Buehrer Virginia Tech Antonio Capone Politecnico di Milano Javier Gómez Castellanos National University of Mexico Claude Castelluccia INRIA Henry Chan The Hong Kong Polytechnic University Ajit Chaturvedi Indian Institute of Technology Kanpur Jyh-Cheng Chen National Tsing Hua University Yong Huat Chew Institute for Infocomm Research Tricia Chigan Michigan Tech Dong-Ho Cho Korea Advanced Institute of Science and Tech. Jinho Choi University of New South Wales Carlos Cordeiro Philips Research USA Laurie Cuthbert Queen Mary University of London Arek Dadej University of South Australia Sajal Das University of Texas at Arlington Franco Davoli DIST University of Genoa Xiaodai Dong, University of Alberta Hassan El-sallabi Helsinki University of Technology Ozgur Ercetin Sabanci University Elza Erkip Polytechnic University Romano Fantacci University of Florence Frank Fitzek Aalborg University Mario Freire University of Beira Interior Vincent Gaudet University of Alberta Jairo Gutierrez University of Auckland Michael Hadjitheodosiou University of Maryland Zhu Han University of Maryland College Park Christian Hartmann Technische Universitat Munchen Hossam Hassanein Queen's University Soong Boon Hee Nanyang Technological University Paul Ho Simon Fraser University Antonio Iera University "Mediterranea" of Reggio Calabria Markku Juntti University of Oulu Stefan Kaiser DoCoMo Euro-Labs Nei Kato Tohoku University Dongkyun Kim Kyungpook National University Ryuji Kohno Yokohama National University Bhaskar Krishnamachari University of Southern California Giridhar Krishnamurthy Indian Institute of Technology Madras Lutz Lampe University of British Columbia Bjorn Landfeldt The University of Sydney Peter Langendoerfer IHP Microelectronics Technologies Eddie Law Ryerson University in Toronto

7,826 citations

Proceedings ArticleDOI
09 Mar 2002
TL;DR: PEGASIS (power-efficient gathering in sensor information systems), a near optimal chain-based protocol that is an improvement over LEACH, is proposed, where each node communicates only with a close neighbor and takes turns transmitting to the base station, thus reducing the amount of energy spent per round.
Abstract: Sensor webs consisting of nodes with limited battery power and wireless communications are deployed to collect useful information from the field. Gathering sensed information in an energy efficient manner is critical to operate the sensor network for a long period of time. In W. Heinzelman et al. (Proc. Hawaii Conf. on System Sci., 2000), a data collection problem is defined where, in a round of communication, each sensor node has a packet to be sent to the distant base station. If each node transmits its sensed data directly to the base station then it will deplete its power quickly. The LEACH protocol presented by W. Heinzelman et al. is an elegant solution where clusters are formed to fuse data before transmitting to the base station. By randomizing the cluster heads chosen to transmit to the base station, LEACH achieves a factor of 8 improvement compared to direct transmissions, as measured in terms of when nodes die. In this paper, we propose PEGASIS (power-efficient gathering in sensor information systems), a near optimal chain-based protocol that is an improvement over LEACH. In PEGASIS, each node communicates only with a close neighbor and takes turns transmitting to the base station, thus reducing the amount of energy spent per round. Simulation results show that PEGASIS performs better than LEACH by about 100 to 300% when 1%, 20%, 50%, and 100% of nodes die for different network sizes and topologies.

3,731 citations