In this paper the parallel conflict-free access to complete extended binary subtrees of complete binary trees is investigated. Thereby linear and also nonlinear memory module assignment functions S are considered. Fur...
详细信息
A method for estimation of the difference in the times of arrival of wavefronts of two separate sensors is introduced. The method, called SPECCORR, exploits the spectral correlation property, called spectral coherence...
详细信息
A method for estimation of the difference in the times of arrival of wavefronts of two separate sensors is introduced. The method, called SPECCORR, exploits the spectral correlation property, called spectral coherence, that essentially all modulated signals exhibit to obtain estimates that are highly tolerant to severely corruptive noise and interference. This tolerance is explained theoretically and demonstrated with simulations.< >
The unifying framework of the spectral-correlation theory of cyclostationary signals is used to present a broad treatment of weak, random signal detection for interception purposes. The relationships among a variety o...
详细信息
The unifying framework of the spectral-correlation theory of cyclostationary signals is used to present a broad treatment of weak, random signal detection for interception purposes. The relationships among a variety of previously proposed ad hoc detectors, optimum detectors, and newly proposed detectors are established. The spectral-correlation-plane approach to the interception problem is put forth as especially promising for detection, classification, and estimation in particularly difficult environments involving unknown and changing noise levels and interference activity. A fundamental drawback of the popular radiometric methods in such environments is explained.
Various types of statistical signal processing require the estimation of time-variant correlation functions and the fitting of time-variant models for nonstationary processes. In this paper, the situations for which n...
详细信息
Various types of statistical signal processing require the estimation of time-variant correlation functions and the fitting of time-variant models for nonstationary processes. In this paper, the situations for which nonstationary probabilistic correlation functions can be accurately estimated from a single sample path of a stochastic process are delineated. These include only (i) known form of nonstationarity, (ii) periodic or almost periodic nonstationarity, and (iii) slowly fluctuating nonstationarity. Known methods of estimation for each of these situations are reviewed within the unifying framework of orthogonal series expansions. The fact that estimators based on orthogonal series expansions for nonstationary correlation functions other than (i)–(iii) cannot be guaranteed to be accurate is established. Ramifications for time-variant autoregressive model fitting are discussed. Verschiedene Aufgabenbereiche der Signalverarbeitung erfordern die Schätzung zeitvarianter Korrelationsfunktionen und die zeitvariante Modellierung nichtstationärer Prozesse. Im folgenden werden die Situationen dargelegt, für die nicht-stationäre Korrelationsfunktionen aus einem einzigen Repräsentanten eines Prozesses geschätzt werden können. Erfaßt werden können nur Fälle mit (i) bekannter Form der Instationarität, (ii) periodischer oder fast-periodischer Instationarität und (iii) langsam veränderlicher Instationarität. Die bekannten Schätzverfahren für jede dieser Gegebenheiten werden in einem einheitlichen Rahmen, dem der Orthogonalreihen-Entwicklung, zusammengestellt. Die Grenzen der Nutzung von Reihenentwicklungen bei der Schätzung nicht-stationärer Korrelationsfunktionen werden aufgezeigt. Variationsmöglichkeiten für die zeitvariante AR-Modellierung werden diskutiert. De nombreuses operations de traitement du signal requièrent l'estimation de fonctions de corrélation dependent du temps et la construction de modèles variant avec le temps pour les processus nonstationnaires. Dans cet a
The ability of a system to classify objects (physical or Abstract) accurately and approximately is essential for performing such Artificial Intelligence tasks as Natural Language processing, Inductive Reasoning, and b...
详细信息
The authors consider the role of noise cancellation and low bit rate speech coding in mobile radio systems. They discuss the reduction of acoustic noise in speech signals, and consider speech-channel coding. Diagrams ...
详细信息
The authors consider the role of noise cancellation and low bit rate speech coding in mobile radio systems. They discuss the reduction of acoustic noise in speech signals, and consider speech-channel coding. Diagrams of signal spectrum are given.< >
It is shown that the frequency-domain transfer functions of general RSC (resistive switched-capacitor) circuits can be determined according to the matrix exponents of the phases. This simplifies the formalism and make...
详细信息
It is shown that the frequency-domain transfer functions of general RSC (resistive switched-capacitor) circuits can be determined according to the matrix exponents of the phases. This simplifies the formalism and makes eigenvalue computation unnecessary. This also makes it possible to derive a stability criterion for general RSC circuits.< >
Techniques have been developed for automated extraction and dynamic interactive display of three-dimensional (3-D) left-ventricular (LV) surface anatomy from cine computer tomography (CT) images using a PC-based image...
详细信息
Techniques have been developed for automated extraction and dynamic interactive display of three-dimensional (3-D) left-ventricular (LV) surface anatomy from cine computer tomography (CT) images using a PC-based image-display architecture. images of both endocardial and myocardial surface anatomy are generated from multiple views at multiple time instances to demonstrate various LV pathologies, including apical akinesis, apical and posterior aneurysms, LV failure, IHSS, and a left atrial myxoma. Surface generation requires interpolation between scans, surface tracking, and rendering. Generation of 60 views corresponding to a single time instance requires approximately 15 minutes. LV dimensions are measured between two or more surface points using one or more views. Dynamic interactive display and measurement of surface anatomy provides a valuable tool for improved understanding and quantitative analysis of LV shape, size, and dimensions in the presence of these pathologies.< >
暂无评论