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CreatorTitleDescriptionSubjectDate
26 Mathews, V. JohnA minimax approach for the joint design of acoustic crosstalk cancellation filtersAbstract-This paper presents a method for jointly designing immersive audio rendering filters for a single listener using loudspeakers. The filters for crosstalk cancellation are assumed to have finite impulse responses and are designed using the minimax criterion. In addition to the traditional At...2007
27 Mathews, V. JohnA new carrier frequency estimator for modem signalsABSTRACT A novel carrier frequency estimation scheme for a relatively broad class of voiceband data signals (modem signals) is presented in this paper. The class of signals being studied includes different types of phase-shift-keyed (PSK) and frequency-shift-keyed (FSK) signals. The frequency estim...1988
28 Mathews, V. JohnA new model of perceptual threshold functions for application in image compression systemsThis paper discusses the development of a perceptual threshold model for the human visual system. The perceptual threshold functions describe the levels of distortions present at each location in an image that human observers can not detect. Models of perceptual threshold functions are useful in ima...1995
29 Simpson, Jamesina J.A novel ELF radar for major oil depositsThis letter proposes a novel extremely low frequency (ELF) radar for major oil deposits. Using our recently developed whole-Earth electromagnetic wave propagation model based upon the finite-difference time-domain method, we have determined that detection of the radial (vertical) component of the sc...2006-01-01
30 Mathews, V. JohnA phase likelihood-based algorithm for blind identification of PSK signalsThis paper presents a phase likelihood-based method for automatically identifying different phase-shift keying (PSK) modulations. This method identifies the PSK signals as the hypothesis for which the likelihood function of phase difference between nearby samples of the received signal is the maximu...2014-01-01
31 Simpson, Jamesina J.A review of progress in FDTD Maxwell's equations modeling of impulsive subionospheric propagation below 300 kHzWave propagation at the bottom of the electromagnetic spectrum (below300 kHz) in the Earth-ionosphere waveguide system has been an interesting and important area of investigation for the last four decades. Such wave propagation is characterized by complex phenomena involving nonhomogeneous and aniso...2007-01-01
32 Furse, Cynthia M.; Gandhi, Om P.A simple convolution procedure for calculating currents induced in the human body for exposure to electromagnetic pulsesAbstract-The finite-difference time-domain (FDTD) and frequency dependent finite difference time-domain (FD)2TD methods have been previously used to calculate internal electric (E) fields and induced currents for exposure of the anatomically based model of the human body to electromagnetic pulses (E...1994
33 Stevens, KennethA single chip low power asynchronous implementation of an FFT algorithm for space applicationsA fully asynchronous _x000C_fixed point FFT processor is introduced for low power space applications. The architecture is based on an algorithm developed by Suter and Stevens specifi_x000C_cally for a low power implementation. The novelty of this architecture lies in its high localization of compo...1998
34 Mathews, V. JohnA stability condition for certain bilinear systemsAbstract-This correspondence derives a simple sufficient condition for the output of a discrete-time, time-invariant bilinear system to be bounded whenever the input signal to the system is bounded by a finite constant.1994
35 Mathews, V. JohnA stability result for RLS adaptive bilinear filtersAbstract- This letter considers recursive least squares (RLS) adaptive nonlinear filtering using bilinear system models. It is shown that the extended RLS adaptive bilinear filter, as well as the equation-error RLS adaptive bilinear filter, are guaranteed to be stable in the sense that the time aver...1994
36 Mathews, V. JohnA stable adaptive Hammerstein filter employing partial orthogonalization of the input signalsAbstract-This paper presents an algorithm that adapts the parameters of a Hammerstein system model. Hammerstein systems are nonlinear systems that contain a static nonlinearity cascaded with a linear system. In this paper, the static nonlinearity is modeled using a polynomial system, and the linear ...2006
37 Mathews, V. John; Dubow, JoelA stable adaptive Hammerstein filter employing partial orthogonalization of the input signalsAbstract This paper presents an algorithm that adapts the parameters of a Hammerstein system model. Hammerstein systems are nonlinear systems that contain a static nonlinearity cascaded with a linear system. In this work, the static nonlinearity is modeled using a polynomial system and the linear f...2002
38 Myers, Chris J.A standard-cell self-timed multiplier for energy and area critical synchronous systemsThis paper describes the design of a standard-cell self-timed multiplier for use in energy and area critical synchronous systems. The area of this multiplier is bounded by N rather than N2 as seen in more traditional combinational parallel array designs, where N is the word size. Energy has a polyn...2001
39 Furse, Cynthia M.A stochastic FDTD method for statistically varying biological tissuesTHE analysis of radio wave absorption is a continuing concern for the cell phone industry due to health effects (and associated regulations) of the person using the cell phone [1,2]. The amount of allowable power absorbed has a strong impact on the design of the phone (antenna, electromagnetic inte...2011
40 Simpson, Jamesina J.A stochastic FDTD model of electromagnetic wave propagation in magnetized ionospheric plasmaCommunications, surveillance, and navigation capabilities rely heavily on accurate knowledge of electromagnetic (EM) signal propagation characteristics through and reflected by the Earth's ionosphere. Satellite communications, over-the-horizon radar, and target direction finding are a few example ap...2013-01-01
41 Mathews, V. JohnA stochastic gradient adaptive filter with gradient adaptive step sizeAbstract-This paper presents an adaptive step-size gradient adaptive filter. The step size of the adaptive filter is changed according to a gradient descent algorithm designed to reduce the squared estimation error during each iteration. An approximate analysis of the performance of the adaptive fil...1993
42 Furse, Cynthia M.A study on the efficiency of transparent patch antennas designed from conductive oxide filmsAbstract? A study on the efficiency of transparent patch antennas designed from indium tin oxide (ITO) films is presented to provide design guidelines for patch type transparent antennas. The trade-offs between optical transparency and antenna efficiency is analyzed by considering typical materia...2011
43 Furse, Cynthia M.A tutorial on Stochastic FDTDThe Stochastic FDTD (S-FDTD) method provides a way to determine the mean and variance of the electric and magnetic fields in a model where the electrical properties (conductivity and permittivity) vary stochastically, from a single S-FDTD simulation. This method is a realistic and more efficient alt...2014-01-01
44 Mathews, V. JohnA unified approach to nonparametric spectrum estimation algorithmsAbstract-Different approaches to spectrum estimation can be broadly classified as parametric and nonparametric methods. In the parametric techniques, an underlying model is assumed in the formulation of the spectrum estimation problem and one estimates the parameters of the model. For nonparametric...1987
45 Mastrangelo, Carlos H.A very high density floating electrode flexible sensor array for high-resolution measurements of contact forcesWe present the development, fabrication and testing results of a new high-density flexible sensor array (HDFA) suitable of recording three-axis stresses with high spatial resolution. The new HDFA consists of 676 (26×26) sensing cells fabricated on top of a high-density flex circuit substrate. Each ...2013-01-01
46 Khan, Faisal HabibAC solar cells: An embedded "all in one" PV power systemPower converters constructed from discrete components are difficult to mass produce, and the installation involves a significant labor cost to have the proper interconnection among the panel, inverter and the grid. These facts indicate that the present PV technology may not be able to address the ch...2012-01-01
47 Simpson, Jamesina J.ADE-FDTD scattered-field formulation for dispersive materialsThis letter presents a scattered-field formulation for modeling dispersive media using the finite-difference time-domain (FDTD) method. Specifically, the auxiliary differential equation method is applied to Drude and Lorentz media for a scattered field FDTD model. The present technique can also be a...2008-01-01
48 Myers, Chris J.; Gopalakrishnan, GaneshAchieving fast and exact hazard-free logic minimization of extended burst-mode gC finite state machinesAbstract This paper presents a new approach to two-level hazard-free logic minimization in the context of extended burst-mode finite state machine synthesis targeting generalized C-elements (gC). No currently available minimizers for literal-exact two-level hazard-free logic minimization of extende...2000
49 Mathews, V. JohnAdaptive algorithms for identifying recursive nonlinear systemsABSTRACT This paper presents two fast least-squares lattice algorithms for adaptive non-linear filters equipped with system models involving nonlinear feedback. Such models can approximate a large class of non-linear systems adequately, and usually with considerable parsimony in the number of coeff...1991
50 Mathews, V. JohnAdaptive bilinear predictorsThis paper considers an extended recursive least squares (RLS) adaptive bilinear predictor. It is shown that the extended RLS adaptive bilinear predictor is guaranteed to be stable in the sense that the time average of the squared a-posteriori prediction error signal is bounded whenever the input...1994
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