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# [1992] IEEE Sixth SP Workshop on Statistical Signal and Array Processing

## Filter Results

Displaying Results 1 - 25 of 127
• ### IEEE Sixth SP Workshop on Statistical Signal and Array Processing Conference Proceedings (Cat. No.92TH0410-1)

Publication Year: 1992
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• ### Non-parametric detection of a class of cyclo-stationary signals in stationary colored non-Gaussian noise using non-stationary higher order spectra

Publication Year: 1992, Page(s):202 - 205
Cited by:  Papers (1)
| | PDF (260 KB)

This paper considers specifically the sum of coherently related narrowband signals of unknown frequencies and amplitudes. It employs the method of non-stationary higher order spectra (NSHOS) and develops a detection statistic based on the non-stationary bispectrum. Within the domain that excludes the stationary HOS, the NSHOS detection statistics as asymptotically zero for any type of stationary c... View full abstract»

• ### Optimal transforms related to path in the time-frequency plane

Publication Year: 1992, Page(s):34 - 37
Cited by:  Papers (1)
| | PDF (216 KB)

This paper shows how to construct integral operators adapted to a given time-frequency energy distribution. The phase function, which is an extension of the phase ωt of the classical Fourier transform, makes it possible to construct an integral operator. The transform is adapted when the partial derivative ∂φ/∂t is the instantaneous frequency of the signal View full abstract»

• ### Application of maximal invariance to adaptive detection with structured and unstructured covariance matrices

Publication Year: 1992, Page(s):251 - 254
| | PDF (292 KB)

The authors introduce a framework for exploring array detection problems in a reduced dimensional space by exploiting the theory of invariance in hypothesis testing. This involves calculating a low dimensional basis set of functions called the maximal invariant, the statistics of which are often tractable to obtain, thereby making analysis feasible and facilitating the search for tests with some o... View full abstract»

• ### Principal component filter banks for optimum wavelet analysis

Publication Year: 1992, Page(s):50 - 53
Cited by:  Papers (7)
| | PDF (272 KB)

Optimality issues are addressed when multiresolution methods are applied to random signals. An optimal P-band perfect reconstruction filter bank is derived, which decomposes the input signal into its lower-resolution principal components. Results are developed for stationary processes and a class of nonstationary processes, which includes cyclostationary signals. FIR designs are discussed and some... View full abstract»

• ### Scale, frequency, time, and the scale transform

Publication Year: 1992, Page(s):9 - 12
Cited by:  Papers (3)
| | PDF (204 KB)

The author develops the relationship between time, frequency, and scale, and their respective operators and representations. A scale operator is proposed and its eigenfunctions are obtained. This leads to the scale transform. The convolution and correlation theorems for scale are developed. The concepts of filtering and linear shift-invariant systems are formulated for scale View full abstract»

• ### Spectral-temporal decomposition of multicomponent signals

Publication Year: 1992, Page(s):206 - 209
Cited by:  Papers (2)
| | PDF (260 KB)

The method is based on autoregressive modeling of the composite signal with an adaptive filter bank. An illustrative example is given for a speech signal View full abstract»

• ### Statistical signal mapping: a general tool for speech signal processing

Publication Year: 1992, Page(s):436 - 439
| | PDF (296 KB)

Various forms of speech processing in practice take, or can be transformed to, the same form of input/output, and the relation of input/output generally can be expressed by a nonlinear function. This paper proposes a framework for identifying statistically the non-linear function concerning the statistical nature of speech. It demonstrates the applicability of this framework in a particular contex... View full abstract»

• ### Analytical observations for DOA estimation performance

Publication Year: 1992, Page(s):318 - 321
| | PDF (264 KB)

The authors study several fundamental relationships of subspace array processing performance to signal measurement conditions. They derive a functional relationship between MSE and each of the following physical data parameters: source correlation, source separation, number of sensors, and number of snapshots. The functional relationships are all derived from their unified MSE expression and allow... View full abstract»

• ### Detection of multiple chirp signals based on a slice of the instantaneous higher-order moments

Publication Year: 1992, Page(s):30 - 33
Cited by:  Papers (1)
| | PDF (276 KB)

A time-frequency (T-F) representation is defined which forces the contribution of the auto terms to appear at fixed positions on the T-F plane, while the cross terms appear at positions that vary depending on the particular slice. The choice of the moment slice is not unique as long as it satisfies certain conditions. Considering different moment slices yields different T-F representations. Summin... View full abstract»

• ### Generalized regularization in cumulant-based parameter estimation

Publication Year: 1992, Page(s):493 - 497
| | PDF (336 KB)

The regularization in third-order cumulant-based parameter estimation is discussed for identification of transfer functions. The SVD-based regularization algorithm to estimate the number of sinusoids in the presence of colored Gaussian noise is given on a basis of fourth-order cumulant. A new MSE-like criterion for determining the optimal multiple adjustable parameters is given to decide the numbe... View full abstract»

• ### Adaptive beams for beamspace direction finding

Publication Year: 1992, Page(s):255 - 258
Cited by:  Papers (2)
| | PDF (248 KB)

Radio direction finding in the high-frequency band is challenging since the complex signal and noise environment is difficult to model, defeating the basis of most high-resolution techniques. Since fixed beams are ineffective with the small apertures common at HF, the authors propose a method for designing beams adaptively (i.e., in a data-dependent manner). Results based on both simulation and re... View full abstract»

• ### Status report on Wavelets in Signal Detection and Identification: Comparative Processing and Technology Evaluation

Publication Year: 1992, Page(s):46 - 49
Cited by:  Papers (1)
| | PDF (288 KB)

The goal of this DARPA program is to compare wavelet techniques with a variety of competing transforms such as the short-time Fourier transforms, the Wigner-Ville transform, constrained total least squares and Prony single-valued decomposition. The comparison domain is the detection and identification of passive underwater transient acoustic signals. This paper focuses on the comparison process. P... View full abstract»

• ### Interference suppression via orthogonal projections

Publication Year: 1992, Page(s):239 - 242
| | PDF (176 KB)

A technique for suppressing interference in phased array antennas, called the orthogonal projection algorithm, is described. Its performance is characterized theoretically and validated using Monte-Carlo simulations. An orthonormal basis for the interference subspace is calculated in the absence of target, and interference is suppressed by projection of the steering vector onto the orthogonal comp... View full abstract»

• ### Geometry of the Cramer-Rao bound

Publication Year: 1992, Page(s):5 - 8
Cited by:  Papers (8)
| | PDF (256 KB)

The Fisher information matrix determines how much information is given by a measurement about the parameters that index the underlying probability distribution. This paper assumes that the parameters structure the mean value vector in a multivariate normal distribution. The Fisher matrix is then a Gramian constructed from the sensitivity vectors that characterize the first-order variation in the m... View full abstract»

• ### Partial discharges in high-voltage transformers

Publication Year: 1992, Page(s):473 - 476
| | PDF (280 KB)

A novel approach to on-line localization of partial discharges in a power transformer is presented. A 2-D technique based on subspace rotation is given. By far-field source and narrowband signal assumptions, the localization problem is reduced to an arrival angle estimation problem. The first step uses two eigenvalue decompositions to clean the data and compute the time delays. The second step con... View full abstract»

• ### Bispectrum based estimation of parameters of Middleton Class A noise

Publication Year: 1992, Page(s):160 - 163
| | PDF (200 KB)

The proposed approach is applicable if the non-Gaussian component of the process has a non-zero mean and a skewed distribution. If the Gaussian background noise is white, it is shown that a linear relationship exists between bispectral magnitude on one frequency axis and the power spectral density of the process. Least squares estimates of the unknowns of the equation can then be obtained, from wh... View full abstract»

• ### Two-dimensional memory nonlinearities and their application to blind deconvolution problems

Publication Year: 1992, Page(s):210 - 212
| | PDF (188 KB)

Blind deconvolution for a nonminimum phase linear time invariant system is possible only if some nonlinear estimates of the input or the higher-order statistics of the output are employed. When the convolutional noise is colored, the optimum estimates becomes memory nonlinear functions of the observations. Closed form solutions for the two-dimensional memory nonlinear MAP estimates depending on on... View full abstract»

• ### Non-iterative blind deconvolution of colored or deterministic signals using higher order cepstra and group delay

Publication Year: 1992, Page(s):132 - 135
Cited by:  Papers (1)
| | PDF (320 KB)

The authors consider an unknown deterministic or nonGaussian nonwhite stochastic signal transmitted through two different unknown LTI mixed phase FIR systems with only noisy observations of the system outputs. The goal is to identify the systems and/or deconvolve the input, to within a magnitude factor and a time delay. The systems must have no zeros on the unit circle and satisfy other mild condi... View full abstract»

• ### Quadratic-inverse estimates of transfer functions

Publication Year: 1992, Page(s):432 - 435
Cited by:  Patents (1)
| | PDF (264 KB)

Estimating transfer functions between time series is essentially regression in the frequency domain but significant differences occur when the available data sequences are short. The author suggests an estimate of transfer functions on narrow, overlapping frequency bands using a quadratic-inverse formalism. (The quadratic-inverse coefficients apply to both an orthogonal expansion of the spectrum a... View full abstract»

• ### The space-time characteristics of brain potentials related to single voluntary movements

Publication Year: 1992, Page(s):322 - 325
| | PDF (316 KB)

Transient time-varying voluntary movement-related potentials reside in non-stationary background EEG activity with signal-to-noise ratios typically below -5 dB. This paper presents the preliminary results of evaluation of the statistical space-time characteristics of single-trial EEG. Its findings show that the variance of the EEG is spatially dependent and has spatially consistent features. The E... View full abstract»

• ### Detection, enumeration, and estimation of multiple co-channel signals

Publication Year: 1992, Page(s):70 - 73
Cited by:  Papers (3)
| | PDF (276 KB)

Coupled digital phase-locked loops derived from extended Kalman filter theory, have been shown to suppress adjacent and co-channel interferers. This paper addresses their ability to separate co-channel signals. State observability criteria are defined and examined for nonlinear state observations which model phase modulation. These metrics can then be used to address signal separation and tracking... View full abstract»

• ### Quadratic time-frequency distributions: the new hyperbolic class and its intersection with the affine class

Publication Year: 1992, Page(s):26 - 29
Cited by:  Papers (7)
| | PDF (336 KB)

The proposed new class of quadratic time-frequency distributions is based on the hyperbolic time shift' and scale invariance properties that are important in the analysis of Doppler invariant signals used in bat and dolphin echolocation, and of locally self-similar' signals used in fractals and fractional Brownian motion. The hyperbolic class can be characterized by 2-D kernels, and kernel const... View full abstract»

• ### Direct estimation of time delay using third-order cumulants

Publication Year: 1992, Page(s):489 - 492
| | PDF (288 KB)

A new method is proposed when the signal is non-Gaussian with nonzero skewness and noises are Gaussian with unknown correlation function. The proposed method finds the time shift which minimizes an error function in the TOC domain where the correlated Gaussian noises are eliminated. Compared with Nikias and Pan's Parametric Bispectrum Method (1988), the proposed method not only has less computatio... View full abstract»

• ### Effect of reduced beamformers on matched-field performance for various array configurations

Publication Year: 1992, Page(s):259 - 262
| | PDF (356 KB)

A modified reduced minimum variance (MRMV) beamformer has been proposed to enhance performance. Computer simulations with and without mismatch are used to investigate the performance of the MV and MRMV beamformers for horizontal, vertical and billboard arrays. With MV processing, mismatch in the form of errors in sensor positions reduced the performance of all array types. Simulations showed the M... View full abstract»