Now showing items 589-608 of 1051

  • Multiscale SAR Image Segmentation using Wavelet-domain Hidden Markov Tree Models 

    Venkatachalam, Vidya; Choi, Hyeokho; Baraniuk, Richard G. (2000-04-01)
    We study the segmentation of SAR imagery using wavelet-domain Hidden Markov Tree (HMT) models. The HMT model is a tree-structured probabilistic graph that captures the statistical properties of the wavelet transforms of ...
  • The Multiscale Structure of Non-Differentiable Image Manifolds 

    Wakin, Michael; Donoho, David; Choi, Hyeokho; Baraniuk, Richard G. (2005-08-01)
    In this paper, we study families of images generated by varying a parameter that controls the appearance of the object/scene in each image. Each image is viewed as a point in high-dimensional space; the family of images ...
  • Multiscale Texture Segmentation of Dip-cube Slices using Wavelet-domain Hidden Markov Trees 

    Magrin-Chagnolleau, Ivan; Choi, Hyeokho; van Spaendonck, Rutger; Steeghs, Philippe; Baraniuk, Richard G. (1999-11-01)
    Wavelet-domain Hidden Markov Models (HMMs) are powerful tools for modeling the statistical properties of wavelet coefficients. By characterizing the joint statistics of wavelet coefficients, HMMs efficiently capture the ...
  • Multiscale Texture Segmentation using Wavelet-domain Hidden Markov Models 

    Choi, Hyeokho; Baraniuk, Richard G. (1998-11-01)
    Wavelet-domain hidden Markov tree (HMT) models are powerful tools for modeling the statistical properties of wavelet transforms. By characterizing the joint statistics of the wavelet coefficients, HMTs efficiently capture ...
  • Multiscale Wedgelet Image Analysis: Fast Decompositions and Modeling 

    Romberg, Justin; Wakin, Michael; Baraniuk, Richard G. (2002-06-01)
    The most perceptually important features in images are geometrical, the most prevalent being the smooth contours ("edges") that separate different homogeneous regions and delineate distinct objects. Although wavelet based ...
  • Multitier Wireless Communications 

    Aazhang, Behnaam; Cavallaro, Joseph R. (2001-06-20)
    Next-generation computing systems will be highly integrated using wireless networking. The Rice Everywhere NEtwork (RENE) project is exploring the integration of WCDMA cellular systems, high speed wireless LANs, and home ...
  • Multitier Wireless Systems 

    Aazhang, Behnaam; Cavallaro, Joseph R. (2000-05-01)
    Next-generation computing systems will be highly integrated using wireless networking. The Rice Everywhere NEtwork (RENE) project is exploring the integration of WCDMA cellular systems, high speed wireless LANs, and home ...
  • Multiuser Channel Estimation and Tracking for Long Code CDMA Systems 

    Bhashyam, Srikrishna; Aazhang, Behnaam (2002-01-15)
    Channel estimation techniques for code-division multiple access (CDMA) systems need to combat multiple access interference (MAI) effectively. Most existing estimation techniques are designed for CDMA systems with short ...
  • Multiuser Channel Estimation for Long Code CDMA Systems 

    Bhashyam, Srikrishna; Aazhang, Behnaam (2000-09-20)
    Channel estimation techniques for code-division multiple access (CDMA) systems need to combat multiple access interference (MAI) effectively. Most existing estimation techniques are designed for CDMA systems with short ...
  • Multiuser detection in fast-fading multipath environments 

    Sayeed, Akbar M.; Sendonaris, Andrew; Aazhang, Behnaam (1998-12-20)
    We propose a new framework for multiuser detection in fast-fading channels that are encountered in many mobile communication scenarios. Existing multiuser RAKE receivers, developed to combat multipath fading and multiuser ...
  • Multiuser detection in fast-fading multipath environments 

    Sayeed, Akbar M.; Aazhang, Behnaam (2001-10-20)
    We propose a new framework for multiuser detection in fast-fading channels that are encountered in many mobile communication scenarios. Existing multiuser RAKE receivers, developed to combat multipath fading and multiuser ...
  • Multiuser detectors for fast-fading multipath channels 

    Sayeed, Akbar M.; Sendonaris, Andrew; Aazhang, Behnaam (1997-10-20)
    We propose a new framework for multiuser detection in fast fading channels that are encountered in many mobile communication scenarios. The detectors proposed in this paper employ a novel multiuser receiver structure based ...
  • Multiuser Information Processing in Wireless Communication 

    Das, Suman (2000-09-20)
    Wireless channel is not very conducive towards error-free raw data transmission. On the other hand the tremendous growth in wireless services has made the channel bandwidth a scarce resource and effective utilization of ...
  • A multiuser receiver for code division multiple access communications over multipath channels 

    Fawer, Urs; Aazhang, Behnaam (1995-02-20)
    A multiuser communication system is considered where K users share a channel with multipath propagation by using code division for multiple access. Data modulation is carried out by binary phase shift keying and direct ...
  • Multiuser receivers for code-division multiple-access systems with trellis-based modulation 

    Fawer, Urs; Aazhang, Behnaam (1996-10-20)
    A code-division multiple-access (CDMA) communication system is studied where a trellis-based scheme is used for data encoding and modulation. The signature sequences (spreading codes), which are assigned to the direct-sequence ...
  • Myoelectric Teleoperation of a Complex Robotic Hand 

    Farry, Kristin A; Walker, Ian D; Baraniuk, Richard G. (1996-10-01)
    Teleoperation continues to be a primary control mode in robotics applications, particularly for robots with complex hands. This paper details a novel method of teleoperation of complex anthropomorphic robotic hands: ...
  • Nanoparticles Heat through Light Localization 

    Hogan, Nathaniel J.; Urban, Alexander S.; Ayala-Orozco, Ciceron; Pimpinelli, Alberto; Nordlander, Peter; Halas, Naomi J. (2014)
    Aqueous solutions containing light-absorbing nanoparticles have recently been shown to produce steam at high efficiencies upon solar illumination, even when the temperature of the bulk fluid volume remains far below its ...
  • Nanowire electrodes for high-density stimulation and measurement of neural circuits 

    Robinson, Jacob T.; Jorgolli, Marsela; Park, Hongkun (2013-03-12)
    Brain-machine interfaces (BMIs) that can precisely monitor and control neural activity will likely require new hardware with improved resolution and specificity. New nanofabricated electrodes with feature sizes and densities ...
  • Near Best Tree Approximation 

    Baraniuk, Richard G.; DeVore, Ronald A.; Kyriazis, George; Yu, Xiang Ming (2002-01-15)
    Tree approximation is a form of nonlinear wavelet approximation that appears naturally in applications such as image compression and entropy encoding. The distinction between tree approximation and the more familiar ...
  • Near-Far Resistant Code Synchronization For CDMA systems - An Implementation Perspective 

    Haller, Bruno; Cavallaro, Joseph R.; Aazhang, Behnaam (1996-04-20)
    In this paper we evaluate and compare several algorithms based on eigenanalysis techniques for near-far resistant code acquisition and tracking, i.e., delay estimation in multiuser CDMA communication systems under different ...