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TitleCreatorDescriptionSubjectDate
226Adaptive phase transform processors for time delay estimationAdaptive phase transform processors for time delay estimationMathews, V. JohnThis paper introduces two recursive realizations of the phase transform (PHAT) processor for time-delay estimation (TDE), using a simple one-pole low-pass filter and the least-mean-square (LMS) adaptive filter, respectively. It is shown that these adaptive methods are capable of tracking time-varyin...1993
227Adaptive polynomial filtersAdaptive polynomial filtersMathews, V. JohnWhile linear filter are useful in a large number of applications and relatively simple from conceptual and implementational view points. there are many practical situations that require nonlinear processing of the signals involved. This article explains adaptive nonlinear filters equipped with polyn...1991
228Adaptive realization of a maximum likelihood time delay estimatorAdaptive realization of a maximum likelihood time delay estimatorMathews, V. JohnABSTRACT This paper presents an adaptive maximum likelihood method for estimating the time difference of arrival of a source signal at two spatially separate sensors. It is well-known that the maximum likelihood technique achieves the Cramer-Rao lower bound for time delay estimation error for ce...1996
229Adaptive realizations of the maximum likelihood processor for time delay estimationAdaptive realizations of the maximum likelihood processor for time delay estimationMathews, V. JohnAbstract-This correspondence introduces an adaptive realization of the maximum likelihood (ML) processor for time delay estimation (TDE). Also presented is a modified ML processor, which requires less computations but still performs better than the other when implemented in an adaptive way. Widrow'...1984
230Adaptive realizations of the phase transform for time delay estimationAdaptive realizations of the phase transform for time delay estimationMathews, V. JohnABSTRACT This paper introduces two recursive realizations of the Phase Transforn (PHAT) processor for tine delay estimation (TOE), using a simple one-pole lowpass filter and the least mean square (LMS) adaptive filter, respectively. It is shown that these adaptive methods are very effective in redu...1984
231Adaptive unsharp masking for contrast enhancementAdaptive unsharp masking for contrast enhancementMathews, V. JohnABSTRACT A new scheme o,f unsharp masking for image contrast enhancement is presented in this paper. An adaptive algorithm is introduced so that a sharpening action is performed only in locations where the image exhibits significant dynamics. Hence, the amplification of noise in smooth areas i...1997
232Adaptive volterra filters using orthogonal structuresAdaptive volterra filters using orthogonal structuresMathews, V. JohnAbstract-This paper presents an adaptive Volterra filter that empolys a recently developed orthogonalization procedure of Gaussian signals for Volterra system identification. The algorithm is capable of handling arbitrary orders of nonlinearity P as well as arbitrary lengths of memory N for the syst...1996
233Adaptive volterra filters using orthogonal structuresAdaptive volterra filters using orthogonal structuresMathews, V. JohnAbstract- This paper presents an adaptive Volterra filter that employs a recently developed orthogonalization procedure of Gaussian signals for Volterra system identification. The algorithm is capable of handling arbitrary orders of nonlinearity P as well as arbitrary lengths of memory N for the sys...1995
234Adaptive, quadratic preprocessing of document images for binarizationAdaptive, quadratic preprocessing of document images for binarizationMathews, V. JohnAbstract-This paper presents an adaptive algorithm for preprocessing document images prior to binarization in character recognition problems. Our method is similar in its approach to the blind adaptive equalization of binary communication channels. The adaptive filter utilizes a quadratic system mod...1998
235Adsorption and desorption of the surfactant Sb on GaInP grown by organometallic vapor phase epitaxyAdsorption and desorption of the surfactant Sb on GaInP grown by organometallic vapor phase epitaxyStringfellow, Gerald B.; Shurtleff, James KevinIt has been determined that ordering has a profound effect on the bandgap energy of many compound semiconductor alloys. Therefore, ordering must be controlled for devices such as solar cells, light emitting diodes and diode lasers. Since ordering depends on the surface properties during organomet...Time dependent surface photoabsorption (SPA); Compound semiconductor alloys2000
236Algebraic curves that work betterAlgebraic curves that work betterTasdizen, TolgaAn algebraic curve is defined as the zero set of a polynomial in two variables. Algebraic curves are practical for modeling shapes much more complicated than conics or superquadrics. The main drawback in representing shapes by algebraic curves has been the lack of repeatability in fitting algebraic...1999
237Algorithms for MIS vector generation and pruningAlgorithms for MIS vector generation and pruningStevens, KennethIgnoring the effect of simultaneous switching for logic gates causes silicon failures for high performance microprocessor designs. The main reason to omit this effect is the run time penalty and potential over-conservatism. Run times are directly proportional to the vector sizes. Efficient algorithm...2006
238An adaptive channel estimator for CDMA systems in multipath fading channelsAn adaptive channel estimator for CDMA systems in multipath fading channelsMathews, V. JohnABSTRACT CDMA systems in multipath fading channels need to estimate channel parameters for coherent detection of the transmitted signals. In this paper we present a simple but effective channel estimation algorithm that can be incorporated into most types of multiuser receivers to obtain good dete...2001
239An analytical model of the perceptual threshold function for multichannel image compressionAn analytical model of the perceptual threshold function for multichannel image compressionMathews, V. JohnABSTRACT The human observer is often the final judge of the quality of compressed images. One way to design a compression system that attempts to reduce or eliminate subjective distortions in the coded images is to incorporate a perceptual threshold function model into the compression system. The...1998
240An asynchronous implementations of the MAXLIST algorithmAn asynchronous implementations of the MAXLIST algorithmMyers, Chris J.ABSTRACT We present an efficient asynchronous VLSI architecture for calculating running maximum or minimum values over a sliding window. Running maximums or minimums are very useful for many signal and image processing tasks. Our architecture performs the calculation using the MAXLIST algorithm. In...1997
241An asynchronous instruction length decoderAn asynchronous instruction length decoderStevens, Kenneth; Myers, Chris J.This paper describes an investigation of potential advantages and pitfalls of applying an asynchronous design methodology to an advanced microprocessor architecture. A prototype complex instruction set length decoding and steering unit was implemented using self-timed circuits. [The Revolving Async...2001
242An asynchronous instruction length decoderAn asynchronous instruction length decoderMyers, Chris J.; Stevens, KennethAbstract-This paper describes an investigation of potential advantages and pitfalls of applying an asynchronous design methodology to an advanced microprocessor architecture. A prototype complex instruction set length decoding and steering unit was implemented using self-timed circuits. [The Revolvi...2001
243An efficient algorithm for joint estimation of differential time delays and frequency offsetsAn efficient algorithm for joint estimation of differential time delays and frequency offsetsMathews, V. JohnABSTRACT This paper introduces an efficient algorithm that jointly estimates differential time delays and frequency offsets between two signals. The approach is a two-step procedure. First, the differential frequency offsets are estimated from measurement of the autocorrelation functions of the rec...1992
244An efficient algorithm for lattice filter/predictorAn efficient algorithm for lattice filter/predictorMathews, V. JohnABSTRACT An efficient method for updating the lattice filter/predictor coefficients using the sign algorithm is introduced. The pertinent coefficients are updated using only the signs of the estimation errors at each stage. This method requires less number of multiplications than other adaptive la...1985
245Polymer based thin film coils as a power module of wireless neural interfacesPolymer based thin film coils as a power module of wireless neural interfacesHarrison, Reid R.For the conventional Utah Electrode Array (UEA) to be able to function without transcutaneous wire connections, a kind of power source is needed in an integrated form with the UEA. To develop such wireless neural interfaces, inductive coupling between two coils was used to deliver power to the integ...Wireless; Neural interfaces; Thin film coils; Utah Electrode Array2006
246The post office experience: designing a large asynchronous chipThe post office experience: designing a large asynchronous chipStevens, KennethThe Post Office is an asynchronous, 300,000 transistor, full-custom CMOS chip designed as the communication component for the Mayfly scalable parallel processor. Performance requirements led to the development of a design style which permits the design of sequential circuits operating under a rest...1993
247Power minimization of a 433-MHz LC VCO for an implantable neural recording systemPower minimization of a 433-MHz LC VCO for an implantable neural recording systemHarrison, Reid R.This paper presents a new random-search based integrated inductor optimization algorithm. The algorithm provides the designer with valuable information about design tradeoffs. it is used to design an inductor to minimize power dissopation in an LC VCO. The measured results show that a 53:1 power sav...2006
248Power, clock, and data recovery in a wireless neural recording devicePower, clock, and data recovery in a wireless neural recording deviceHarrison, Reid R.For many medical applications, neural recording systems should be fully implantable. Transcutaneous wires must be compleley eliminated, and this necessitates the wireless transfer of power, clock and configuration data to the device. We have developed, fabricated, and tested cirucits that recover po...2006
249Practical verification and synthesis of low latency asynchronous systemsPractical verification and synthesis of low latency asynchronous systemsStevens, KennethA new theory and methodology for the practical verification and synthesis of asynchronous systems is developed to aid in the rapid and correct implementation of complex control structures. Specifications are based on a simple process algebra called CCS that is concise and easy to understand and use....1994
250Predicted MIMO performance in intra-vehicle channelsPredicted MIMO performance in intra-vehicle channelsFurse, Cynthia M.Wireless sensor networks inside vehicles face particularly harsh multipath and shadowing constraints. The closed or semi-closed metallic structure functions much like a reverberation chamber, but with some regions shielded from other regions. Vehicles (particularly aircraft) often have extremely hig...2008-07
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