The radar returns from some classes of time-varying point targets can be represented by the discrete-time signal plus noise model: x(t) = s(t) + [nu(t) + eta(t)] = (P-1)Sigma(i=0) A(i)e(j2 pi fi/fst) + nu(t) + eta(t),...
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ISBN:
(纸本)0819425842
The radar returns from some classes of time-varying point targets can be represented by the discrete-time signal plus noise model: x(t) = s(t) + [nu(t) + eta(t)] = (P-1)Sigma(i=0) A(i)e(j2 pi fi/fst) + nu(t) + eta(t), t is an element of 0,...,.N - 1, f(i) = kf(I) + f(o) where the received signal x(t) corresponds to the radar return from the target of interest from one azimuth-range cell. The signal has an unknown number of components, P, unknown complex amplitudes A(i) and frequencies f(i). The frequency parameters f(o) and f(I) are unknown, although constrained such that f(o) < fI/2 and parameter k is an element of {-u,...,-2,-1,0,1,2,...,upsilon) is constrained such that the component frequencies f(i) are bound by [-fs/2,fs/2). The noise term nu(t), is typically coloured, and represents clutter, interference and various noise sources. It is unknown, except that Sigma(t)\nu(t)\(2) < infinity;in general, nu(t) is not well modelled as an auto-regressive process of known order. The additional noise term eta(t) represents time-invariant point targets in the same azimuth-range cell. An important characteristic of the target is the unknown parameter, f(I), representing the frequency interval between harmonic lines. It is desired to determine an estimate of f(I) from N samples of x(t). We propose an algorithm to estimate f(I) based on Thomson's harmonic line F-Test, which is part of the multi-window spectrum estimation method and demonstrate the proposed estimator applied to target echo time series collected using an experimental HF skywave radar.
The proceedings include 28 papers, 27 of them are indexed separately. Topics covered include advanced techniques of real-time signalprocessing in various fields, such as space information systems, radar data processi...
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The proceedings include 28 papers, 27 of them are indexed separately. Topics covered include advanced techniques of real-time signalprocessing in various fields, such as space information systems, radar data processing, missile guidance underwater acoustic imaging, wideband integrated optics. Also hardware architectures and algorithms for real-time signalprocessing are considered. Several presentations are devoted to digital approaches and analog implementations of real-time signalprocessing.
Elliptic Curve Cryptography have known, in recent years, an increasing success in security applications thanks to their advantages such as a short keys size with a high security level. Their popularity has led to vari...
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ISBN:
(纸本)9781467385268
Elliptic Curve Cryptography have known, in recent years, an increasing success in security applications thanks to their advantages such as a short keys size with a high security level. Their popularity has led to various implementations in terms of algorithms, curves, coordinate systems, platforms, etc. The aim of this work is first to explore actual trends of ECC-based implementations in different platforms through a review of a number of works. Secondly, to identify and gather the criteria and corresponding metrics used to evaluate the performance of these implementations. We also propose a platform for design exploration and evaluation of ECC designs.
A number of adaptive condition number estimators have been proposed in the past to dynamically estimate the sensitivity of the coefficient matrix of a linear systems of equations. Applications of these techniques ofte...
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ISBN:
(纸本)0819416207
A number of adaptive condition number estimators have been proposed in the past to dynamically estimate the sensitivity of the coefficient matrix of a linear systems of equations. Applications of these techniques often arise in the context of signalprocessing, where the information matrix is being updated with rank-one modifications. Various schemes, such as ACE, ALE and ICE, were proposed to cope with this problem. In this paper, we will briefly review the past work, and show how the small-sample condition estimator can be used in an adaptive manner.
Wireless sensor networks present a number of challenges to system designers, including notably the efficient use of limited resources such as bandwidth and energy. One way these challenges can be addressed is through ...
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Wireless sensor networks present a number of challenges to system designers, including notably the efficient use of limited resources such as bandwidth and energy. One way these challenges can be addressed is through the application of signalprocessing principles in the design, deployment and operation of sensor networks. After a discussion of general issues arising in this context, this talk will describe several recent developments in this area. These include the effects of receiver choice on energy efficiency, collaborative beam-forming, sensor scheduling, and distributed learning. Some of the work described in this talk can be found in Refs. 1-8.
This paper describes research into a high speed image processing system using parallel digital signal processors for the processing of electro-optic images. The objective of the system is to reduce the processing time...
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ISBN:
(纸本)0819416207
This paper describes research into a high speed image processing system using parallel digital signal processors for the processing of electro-optic images. The objective of the system is to reduce the processing time of non-contact type inspection problems including industrial and medical applications. A single processor can not deliver sufficient processing power required for the use of applications hence, a MIMD system is designed and constructed to enable fast processing of electro-optic images. The Texas Instruments TMS320C40 digital signal processor is used due to its high speed floating point CPU and the support for the parallel processing environment. A custom designed VISION bus is provided to transfer images between processors. The system is being applied for solder joint inspection of high technology printed circuit boards.
The well-known uncertainty principle is often invoked in signalprocessing. It is also often considered to have the same implications in signal analysis as does the uncertainty principle in quantum mechanics. The unce...
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ISBN:
(纸本)0819406945
The well-known uncertainty principle is often invoked in signalprocessing. It is also often considered to have the same implications in signal analysis as does the uncertainty principle in quantum mechanics. The uncertainty principle is often incorrectly interpreted to mean that one cannot locate the time-frequency coordinates of a signal with arbitrarily good precision, since, in quantum mechanics, one cannot determine the position and momentum of a particle with arbitrarily good precision. Renyi information of the third order is used to provide an information measure on time-frequency distributions. The results suggest that even though this new measure tracks time-bandwidth results for two Gabor log-ons separated in time and/or frequency, the information measure is more general and provides a quantitative assessment of the number of resolvable components in a time frequency representation. As such, the information measure may be useful as a tool in the design and evaluation of time-frequency distributions.
A two-sided (or complete) orthogonal decomposition of an m × n matrix A is a product of an orthogonal matrix, a triangular matrix, and another orthogonal matrix. Two examples are the URV and ULV decompositions. I...
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ISBN:
(纸本)0819416207
A two-sided (or complete) orthogonal decomposition of an m × n matrix A is a product of an orthogonal matrix, a triangular matrix, and another orthogonal matrix. Two examples are the URV and ULV decompositions. In this paper we present and analyze URV and ULV algorithms that are efficient whenever the numerical rank k of the matrix is much less than min(m,n). We also prove that good estimates of the singular vectors, needed in the algorithms, lead to good approximations of the singular subspaces of A.
作者:
Waltz, Frederick M.3M Company
Engineering Systems and Technology Laboratories 3M Center Building 518-1-01 Saint PaulMN55144 United States
The median filter is one widely-used member of the class of ranked-intensity filters. Such filters are useful in signalprocessing, and particularly in machine vision, because they effectively remove an important and ...
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Measurement of EEG event-related potential (ERP) data has been most commonly undertaken in the time-domain, which can be complicated to interpret when separable activity overlaps in time. When the overlapping activity...
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ISBN:
(纸本)9780819472946
Measurement of EEG event-related potential (ERP) data has been most commonly undertaken in the time-domain, which can be complicated to interpret when separable activity overlaps in time. When the overlapping activity has distinct frequency characteristics, however, time-frequency (TF) signalprocessing techniques can be useful. The current report utilized ERP data from a cognitive task producing typical feedback-related negativity (FRN) and P300 ERP components which overlap in time. TF transforms were computed using the binomial reduced interference distribution (RID), and the resulting TF activity was then characterized using principal components analysis (PCA). Consistent with previous work, results indicate that the FRN was more related to theta activity (3-7 Hz) and P300 more to delta activity (below 3 Hz). At the same time, both time-domain measures were shown to be mixtures of TF theta and delta activity, highlighting the difficulties with overlapping activity. The TF theta and delta measures, on the other hand, were largely independent from each other, but also independently indexed the feedback stimulus parameters investigated. Results support the view that TF decomposition can greatly improve separation of overlapping EEG/ERP activity relevant to cognitive models of performance monitoring.
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