Fourth Annual ASSP Workshop on Spectrum Estimation and Modeling

3-5 Aug. 1988

Filter Results

Displaying Results 1 - 25 of 81
  • Fourth Annual ASSP Workshop on Spectrum Estimation and Modeling (Cat. No.88CH2633-6)

    Publication Year: 1988
    Request permission for commercial reuse | |PDF file iconPDF (30 KB)
    Freely Available from IEEE
  • Where do we stand on high resolution in low-angle tracking radar?

    Publication Year: 1988
    Cited by:  Papers (4)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (56 KB)

    Summary form only given. Various issues involved in the achievement of high resolution in low-angle tracking radar are reviewed. Particular attention is given to the multipath phenomenon, the use of high-resolution beamforming, estimation techniques, nonredundant arrays, results obtained with a multiparameter adaptive radar system, and future plans for adaptive matched illumination and adaptive di... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High-order spectra of mixture processes

    Publication Year: 1988
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (74 KB)

    Summary form only given. In certain processes higher-order spectra reveal more information than second-order spectra. For example, the bispectrum has been applied to determine deviations from Gaussianness, to determine phase information in nonGaussian linear processes, and in nonlinear interactions. The trispectrum has also been used to extract phase information from nonGaussian signals. For the p... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Subspace linear prediction approach to extracting poles

    Publication Year: 1988, Page(s):367 - 370
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (199 KB)

    It is shown that the conventional linear prediction (LP) methods (including various versions of the Prony method) and the matrix pencil method for extracting poles of data sequences can be unified under a generalized approach called the subspace linear prediction (SLP) approach. The conventional LP methods can be considered as high-order SLP methods, while the matrix pencil method is a first-order... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An alternative method of beamforming in the presence of correlated arrivals

    Publication Year: 1988, Page(s):356 - 361
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (364 KB)

    Correlation between desired signal and unwanted interference can severely degrade the performance of an antenna array system. The author proposes a method to decorrelate the two sources and derives analytical expressions to show the decorrelation effect of the proposed technique. The proposed method makes use of an estimate of L×L dimensional array correlation matrix with ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Transfer function phase estimation using a low variance higher order spectrum

    Publication Year: 1988, Page(s):217 - 222
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (424 KB)

    A method is presented for identifying a linear system from observations of the output only. The authors introduce a new one-dimensional spectrum, P(ω), and use it to obtain the underlying linear system. The proposed method incorporates builtin smoothing mechanisms to reduce the variance of the phase. The proposed approach requires fewer computations that the Lii-Rosenblatt approach (1982), a... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A new method to estimate the direction of arrival of signals

    Publication Year: 1988, Page(s):108 - 110
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (192 KB)

    The authors propose a new method for estimating the direction of arrival for cases where the noise is white or colored. The algorithm for estimating the direction of arrival requires only the solution of a polynomial equation whose degree is just equal to the number of signals. The estimate is strongly consistent under minimal moment restrictions. Simulation results for the proposed method are pre... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High resolution sensor array signal processing in the beamspace domain: novel techniques based on the poor resolution of Fourier beamforming

    Publication Year: 1988, Page(s):350 - 355
    Cited by:  Papers (7)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (584 KB)

    The prospect of sensor array signal processing in beamspace, as opposed to element space, is proposed for the purpose of advantageously exploiting the poor resolution of classical beamforming to convert the element space data vectors to beamspace data vectors having a higher signal/noise ratio and a lower dimensionality. The higher SNR facilities sub-beamwidth resolution capability while the lower... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Uniqueness considerations in autoregressive modeling with third moments

    Publication Year: 1988, Page(s):213 - 216
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (192 KB)

    The authors note that Yule-Walker equations for autoregressive (AR) modeling with second-moment (auto-correlation) sequences provide necessary and sufficient conditions for exact matching of the autocorrelation samples of a discrete stationary random process with that of the model. However, when AR modeling is done with linear equations that satisfy the necessary conditions for a match between sam... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Maximum likelihood estimation of a linearly structured covariance with application to antenna array processing

    Publication Year: 1988, Page(s):172 - 175
    Cited by:  Papers (31)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (324 KB)

    The author considers the maximum-likelihood (ML) estimation of the covariance of a zero-mean Gaussian random vector from its samples, when the covariance has a certain known structure that typically arises in antenna array processing. Owing to this structure, the conventional sample covariance is no longer the ML estimator. While previous approaches to ML estimation of similar structured covarianc... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Special techniques for the estimation of the ACF of spherically invariant random processes

    Publication Year: 1988, Page(s):379 - 382
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (212 KB)

    A class of correlation estimates for complex spherically invariant random processes is introduced as an extension of the polarity coincidence correlator estimate. Their accuracy is for reference cases, and some experimental results are provided. Some hybrid estimators based on an extension of the Bussgang theorem are briefly reviewed. The computational advantages of the proposed estimators are out... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • High resolution spectral estimation through localized polynomial approximation

    Publication Year: 1988, Page(s):402 - 407
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (360 KB)

    Autoregressive-moving-average models are not adequate for most tomographic imaging reconstruction problems. Consequently, the high-resolution capability being sought is lost when these models are used. In this work, a model based on localized polynomial approximation of the spectrum is proposed to solve this class of spectral estimation problems. A method for finding the model parameters is give, ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance analysis of eigenvector-based high resolution estimators for direction finding in correlated and coherent scenes

    Publication Year: 1988, Page(s):103 - 107
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (404 KB)

    The authors present an asymptotic analysis of a class of high-resolution estimators for resolving correlated and coherent plane waves in noise. These estimators are constructed from certain eigenvectors associated with spatially smoothed (or unsmoothed) covariance matrices. The analysis is first carried out for the smoothed case, and from this the conventional MUSIC (unsmoothed) scheme is derived ... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Model based spectrum estimation for planar array signal processing

    Publication Year: 1988, Page(s):344 - 349
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (488 KB)

    The authors present two-dimensional (2-D) random field modeling for the estimation of the power spectral density function of planar array data. They review noncausal autoregressive and Gaussian Markov random field modeling of stationary 2-D random processes. A method for obtaining robust parameter estimates in the nonGaussian situation is also presented. The application of 2-D method model-based s... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimal estimates of MA and ARMA parameters of non-Gaussian processes from high-order cumulants

    Publication Year: 1988, Page(s):208 - 212
    Cited by:  Papers (8)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (336 KB)

    The authors describe an asymptotically minimum-variance algorithm for estimating the moving average (MA) and autoregressive moving average (ARMA) parameters of nonGaussian processes from sample second- and third-order moments. The algorithm uses the statistical properties (covariances and cross-covariances) of the sample moments explicitly. An alternative, simpler algorithm is also presented, whic... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • ARMA parameter estimation using only output cumulants

    Publication Year: 1988, Page(s):193 - 198
    Cited by:  Papers (12)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (456 KB)

    The authors develop two algorithms to estimate the parameters of a nonminimum phase autoregressive moving average (ARMA) system which is excited by an unobservable i.i.d. nonGaussian process. AR parameters are obtained in the usual way-via the higher-order Yule-Walker equations based either on the autocorrelations or the cumulants. The first method uses q (where q is the MA order... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Frequency estimation by adaptive notch-filtering in cascade/parallel form

    Publication Year: 1988, Page(s):44 - 48
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (344 KB)

    A novel algorithm is presented for frequency estimation of sinusoids in noise. A priori knowledge of relations between the sinusoid frequencies (e.g. harmonics) is incorporated into the procedure, resulting in a single parameter estimation. The special ARMA system used-the notch filter-is implemented in cascade/parallel form with independent second-order sections. The update for each section is do... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Structured covariance matrices and dimensionality reduction in array processing

    Publication Year: 1988, Page(s):168 - 171
    Cited by:  Papers (18)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (316 KB)

    Data are often passed through rectangular matrix transformations in adaptive beamforming and direction-of-arrival estimation to reduce data dimension and lower computational load. The authors show that the transformation defines a structured model for the full dimension data covariance matrix. Signal processing applied to the reduced dimension data is equivalent to processing the original data whi... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Distributed AR spectral estimation

    Publication Year: 1988, Page(s):376 - 378
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (188 KB)

    The author studies the problem of combining in an optimal fashion autoregressive (AR) model-based spectral estimates obtained at geographically dispersed sites under the assumptions that the data are Gaussian AR(p), all sites fit the data to a p-order all-pole model where p is a given integer known to all sensors and to the fusion center, and the amount of data collected at each site is l... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • ARMA modeling based on partial AR and MA parameter approximation

    Publication Year: 1988, Page(s):397 - 401
    Cited by:  Papers (1)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (256 KB)

    A transfer-function modeling concept is developed for an unknown casual stable, linear-time invariant system. The approach taken has been to treat the models separately and then to achieve the general autoregressive-moving-average (ARMA) transfer function representation. The AR approach has been obtained from conventional methods of the Yule-Walker formulations and associated Levinson-Durbin algor... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effects of sensor position and pattern perturbations on CRLB for direction finding of multiple narrow-band sources

    Publication Year: 1988, Page(s):98 - 102
    Cited by:  Papers (20)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (252 KB)

    The authors study the effects of sensor pattern and sensor position perturbations on the angle estimation performance bound for multiple narrow-band sources. The Cramer-Rao lower bound (CRLB) is used with a probabilistic modeling of the perturbations. The CRLBs of a linear uniform array under sensor position and pattern perturbations are evaluated in detail for the case of two narrowband sources View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Strong consistency of recursive least square estimates on amplified harmonics for line spectrum

    Publication Year: 1988, Page(s):246 - 249
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (212 KB)

    For a sampled signal with length n, it is shown that the method of maximum least-squares regressions on amplified harmonics yields estimates for discrete frequencies with the variance of order n -3 and with the bias of an order almost surely smaller than n -3/2 (log n)1/2+δ. Hence, these estimates are strongly consistent and very accurate. It is show... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A 2-D spectral estimation approach for source detection in array processing

    Publication Year: 1988, Page(s):339 - 343
    Cited by:  Papers (3)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (268 KB)

    The source detection problem in array processing is studied in the case where the two-parameter (2-D) process y(m,n) representing the signal on the sensor n, sampled at time m, is stationary. In this case the spectral measure of y is a singular measure carried by straight lines that are related to the directional parameters of the sources. As in the well-known Pisarenko method, it is shown that th... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Robust decentralized direction-of-arrival estimation in the presence of outlier contaminated noise

    Publication Year: 1988, Page(s):117 - 122
    Cited by:  Papers (2)
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (484 KB)

    A novel scheme for direction-of-arrival estimation is presented. In particular, the authors develop a procedure that provides estimates that are robust against outliers and distributional uncertainties. It also employs decentralized processing such that each subarray provides a set of robust estimates of the directions-of-arrival accompanied by some confidence measures of the estimates. At the fus... View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Spectrum estimation via maximum likelihood estimation of Toeplitz constrained covariances

    Publication Year: 1988, Page(s):182 - 185
    Request permission for commercial reuse | Click to expandAbstract |PDF file iconPDF (272 KB)

    The authors apply the maximum-likelihood (ML) method to the estimation of Toeplitz constrained covariances from Gaussian processes. An iterative expectation-maximization algorithm is used to generate the maximizers, and performance results are shown, demonstrating the superior mean-squared error properties of the ML estimator to conventional covariance estimates View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.