Now showing items 450-469 of 508

  • Throughput Maximization for ARQ-like Systems in Fading Channels with Coding and Queuing Delay Constraints 

    Ahmed, Nadeem; Baraniuk, Richard G. (2004-11-01)
    Practical delay-limited communication systems often employ retransmission algorithms such as ARQ to ensure reliable communications in fading channels. Maximizing the communications throughput in such systems can cause ...
  • Throughput Measures for Delay-constrained Communications in Fading Channels 

    Ahmed, Nadeem; Baraniuk, Richard G. (2003-10-01)
    Fading channels, often seen in wireless systems, provide an unfavorable environment for reliable communications. Current methods for evaluating the performance of fading channels include ergodic capacity and <i>epsilon</ ...
  • Time Frequency Analysis Applications in Geophysics 

    Steeghs, Philippe; Baraniuk, Richard G.; Odegard, Jan E. (2002-01-15)
    In this chapter, we overview a number of applications of time-frequency representations in seismic data processing, from the analysis of seismic sequences to efficient attribute extraction to 3-D attributes for volumetric data.
  • Time Frequency Detectors 

    Sayeed, Akbar M.; Jones, Douglas L. (1996-01-20)
    Time-frequency representations (TFRs) provide a powerful and flexible structure for designing optimal detectors in a variety of nonstationary scenarios. In this paper, we describe a TFR-based framework for optimal detection ...
  • Time Frequency Principal Components: Application to Speaker Identification 

    Magrin-Chagnolleau, Ivan; Durou, Geoffrey (1999-01-01)
    In this paper, we propose a formalism, called vector filtering of spectral trajectories, which allows to integrate under a common formalism a lot of speech parameterization approaches. We then propose a new filtering in ...
  • Time-Frequency Complexity and Information 

    Flandrin, Patrick; Baraniuk, Richard G.; Michel, Olivier (1994-04-01)
    Many functions have been proposed for estimating signal information content and complexity on the time-frequency plane, including moment-based measures such as the time-bandwidth product and the Shannon and Renyi entropies. ...
  • Time-frequency analysis of seismic sequences 

    Steeghs, Philippe; Drijkoningen, Guy G (1995-01-15)
    Reflection patterns play an important role in seismic sequence stratigraphy, therefore making their quantitative description essential for the construction and validation of sequence stratigraphic models from seismic data. ...
  • Time-Frequency Based Distance and Divergence Measures 

    Michel, Olivier; Baraniuk, Richard G. (1994-10-01)
    A study of the phase and amplitude sensitivity of the recently proposed Renyi time-frequency information measure leads to the introduction of a new "Jensen-like" divergence measure. While this quantity promises to be a ...
  • TIME-FREQUENCY SIGNAL PROCESSING ALGORITHMS: ANALYSIS AND SYNTHESIS USING WIGNER DISTRIBUTIONS 

    BOUDREAUX-BARTELS, GLORIA FAYE (1984)
    A tutorial review of several mixed time-frequency representations of signals and systems is presented. Emphasis is placed on the background, extensions, inter-relationships, and applications of the Gabor logon, the Short-time ...
  • Time-Selective Signaling and Reception for Communication over Multipath Fading Channels 

    Bhashyam, Srikrishna; Sayeed, Akbar M.; Aazhang, Behnaam (2000-01-20)
    The mobile wireless channel affords inherent diversity to combat the effects of fading. Existing code division multiple access (CDMA) systems, by virtue of spread-spectrum signaling and RAKE reception, exploit only part ...
  • Toward a theory of information processing 

    Sinanovic, Sinan; Johnson, Don (2004-06-01)
    Information processing theory endeavors to quantify how well signals encode information and how well systems, by acting on signals, process information. We use information-theoretic distance measures, the Kullback-Leibler ...
  • Toward an Improved Understanding of Network Traffic Dynamics 

    Riedi, Rudolf H.; Willinger, Walter (1999-06-20)
    Since the discovery of long range dependence in Ethernet LAN traces there has been significant progress in developing appropriate mathematical and statistical techniques that provide a physical-based, networking-related ...
  • Toward an Improved Understanding of Network Traffic Dynamics 

    Riedi, Rudolf H.; Willinger, Walter (2000-01-15)
    Since the discovery of long range dependence in Ethernet LAN traces there has been significant progress in developing appropriate mathematical and statistical techniques that provide a physical-based, networking-related ...
  • Transmit Spectra Adaptive to Noise and Interference at Activation for HDSL2 

    Gaikwad, Rohit; Baraniuk, Richard G. (1998-01-15)
    We present several methods for implementing optimal HDSL2 transmit spectra that, at activation, adapt to the surrounding interference and noise. The methods are based around either a set of fixed transmit filters or a ...
  • Truncated on-line arithmetic with applications to communication systems 

    Rajagopal, Sridhar; Cavallaro, Joseph R. (2006-09-01)
    Truncation and saturation in digit-precision are very important and common operations in embedded system design for bounding the required finite precision and for area-time-power savings. In this paper, we present the use ...
  • Tuning support vector machines for minimax and Neyman-Pearson classification 

    Scott, Clayton D.; Baraniuk, Richard G.; Davenport, Mark A. (2008-08-19)
    This paper studies the training of support vector machine (SVM) classifiers with respect to the minimax and Neyman-Pearson criteria. In principle, these criteria can be optimized in a straightforward way using a cost-sensitive ...
  • Unitary Equivalence and Signal Processing 

    Baraniuk, Richard G.; Jones, Douglas L. (1993-08-01)
    The notions of time, frequency, and scale are generalized using concepts from unitary operator theory and eigenanalysis. The result is an infinite number of new signal analysis and processing tools that are implemented ...
  • Unitary Equivalence: A New Twist on Signal Processing 

    Baraniuk, Richard G.; Jones, Douglas L. (1995-10-01)
    Unitary similarity transformations furnish a powerful vehicle for generating infinite generic classes of signal analysis and processing tools based on concepts different from time, frequency, and scale. Implementation of ...
  • Universal Distributed Sensing via Random Projections 

    Wakin, Michael; Duarte, Marco F.; Baraniuk, Richard G.; Baron, Dror (2006-04-01)
    This paper develops a new framework for distributed coding and compression in sensor networks based on distributed compressed sensing (DCS). DCS exploits both intra-signal and inter-signal correlations through the concept ...
  • Unsupervised SAR Image Segmentation using Recursive Partitioning 

    Baraniuk, Richard G. (2000-04-01)
    We present a new approach to SAR image segmentation based on a Poisson approximation to the SAR amplitude image. It has been established that SAR amplitude images are well approximated using Rayleigh distributions. We show ...