Now showing items 466-485 of 508

  • 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 ...
  • Useful Facts about the Kullback-Leibler Discrimination Distance 

    Lexa, Michael (2004-12-01)
    This report contains a list of some of the more prominent properties and theorems concerning the Kullback-Leibler (KL) discrimination distance. A brief discussion is also provided indicating the type of problems in which ...
  • Variable-Rate Universal Slepian-Wolf Coding with Feedback 

    Sarvotham, Shriram; Baron, Dror; Baraniuk, Richard G. (2005-11-01)
    Traditional Slepian-Wolf coding assumes known statistics and relies on asymptotically long sequences. However, in practice the statistics are unknown, and the input sequences are of finite length. In this finite regime, ...
  • VLSI Architectures for Multitier Wireless Systems 

    Cavallaro, Joseph R. (1999-11-20)
    Next-generation computing systems will be highly integrated using wireless networking. The Rice Everywhere NEtwork (RENÃ ) project is exploring the integration of WCDMA cellular systems, high speed wireless LANs, and home ...
  • Volterra Filter Identification Using Penalized Least Squares 

    Nowak, Robert David (1996-05-20)
    Volterra filters have been applied to many nonlinear system identification problems. However, obtaining good filter estimates from short and/or noisy data records is a difficult task. We propose a penalized least squares ...
  • W-CDMA real-time algorithm implementation and evaluation 

    Jones, Bryan Allen (2000-05-20)
    This paper describes a platform to enable and explore the design and implementation of next-generation CDMA wireless base stations. A DSP and FPGA-based multiprocessor board is integrated into a Simulink-based wireless ...
  • Warped Perspectives in Time Frequency Analysis 

    Baraniuk, Richard G. (1994-10-01)
    Unitary similarity transformations furnish a simple yet powerful vehicle for generating new classes of joint distributions based on concepts different from time, frequency, and scale. These new signal representations ...
  • Warped Wavelet Bases: Unitary Equivalence and Signal Processing 

    Baraniuk, Richard G.; Jones, Douglas L. (1993-04-01)
    The notions of time, frequency, and scale are generalized using concepts from unitary operator theory and applied to time-frequency analysis, in particular the wavelet and short-time Fourier transform orthonormal bases and ...
  • WAVEFORM ANALYSIS USING DIGITAL TECHNIQUE 

    GOTTLIEB, ELIEZER (1967)
  • Wavelet -Based Statistical Signal Processing using Hidden Markov Models 

    Crouse, Matthew; Nowak, Robert David; Baraniuk, Richard G. (1998-04-01)
    Wavelet-based statistical signal processing techniques such as denoising and detection typically model the wavelet coefficients as independent or jointly Gaussian. These models are unrealistic for many real-world signals. ...
  • Wavelet Analysis of Fractional Brownian Motion in Multifractal Time 

    Goncalves, Paulo; Riedi, Rudolf H. (1999-09-20)
    We study <i>fractional Brownian motions in multifractal time</i>, a model for multifractal processes proposed recently in the context of economics. Our interest focuses on the statistical properties of the wavelet decomposition ...
  • Wavelet Based SAR Speckle Reduction and Image Compression 

    Odegard, Jan E.; Guo, Haitao; Lang, Markus; Burrus, C. Sidney; Wells, R.O.; Novak, L.M.; Hiett, M. (1995-04-01)
    This paper evaluates the performance of the recently published wavelet based algorithm for speckle reduction of SAR images. The original algorithm, based on the theory of wavelet thresholding due to Donoho and Johnstone, ...
  • Wavelet Based SAR Speckle Reduction and Image Compression 

    Odegard, Jan E.; Guo, Haitao; Lang, Markus; Burrus, C. Sidney; Wells, R.O.; Novak, L.M.; Hiett, M. (1995-01-15)
    This paper evaluates the performance of the recently published wavelet based algorithm for speckle reduction of SAR images. The original algorithm, based on the theory of wavelet thresholding due to Donoho and Johnstone, ...
  • Wavelet Based Speckle Reduction with Applications to SAR based ATD/R 

    Guo, Haitao; Odegard, Jan E.; Lang, Markus; Gopinath, Ramesh A.; Selesnick, Ivan W.; Burrus, C. Sidney (1994-11-20)
    This paper introduces a novel speckle reduction method based on thresholding the wavelet coefficients of the logarithmically transformed image. The method is computational efficient and can sinificantly reduce the speckle ...
  • Wavelet Domain Filtering for Nuclear Medicine Imaging 

    Nowak, Robert David; Baraniuk, Richard G. (1996-11-01)
    The authors propose a new filtering/estimation method for nuclear medicine imaging. The statistical method of cross-validation is used to design optimal wavelet domain filters for improved image estimation. The quality of ...
  • Wavelet Folding and Decorrelation Across the Scale 

    Baraniuk, Richard G.; Wells, R.O.; Tian, Jun Feng (2000-06-01)
    The discrete wavelet transform (DWT) gives a compact multiscale representation of signals and provides a hierarchical structure for signal processing. It has been assumed the DWT can fairly well decorrelate real-world ...
  • Wavelet Soft-Thresholding of Time-Frequency Representations 

    Baraniuk, Richard G. (1994-11-01)
    The high noise sensitivity of the Wigner distribution makes smoothing a necessity for producing readable time-frequency images of noise corrupted signals. Since linear smoothing suppresses noise at the expense of considerable ...