The aim of this paper is to apply an algorithm related to the rational approximation for the identification of the lag structure in a transfer-function model. In fact, we apply the ε-algorithm proposed by Berlinet [3...
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Different from conventional spaceborne or airborne synthetic aperture radar(SAR) with optimal aperture length, an imaging radar with highly suboptimal aperture length acquires the data in short bursts by a geometry sp...
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Different from conventional spaceborne or airborne synthetic aperture radar(SAR) with optimal aperture length, an imaging radar with highly suboptimal aperture length acquires the data in short bursts by a geometry spreading over a large range. A polarlike or pseudopolar format grid is introduced to sample data close to the resolution, which presents the design of a separable kernel for efficient FFT *** proposed imaging algorithm formulates the reflectivity image of the target scene as an interpolation-free double image series expansion with two usual approximation-induced phase error terms being taken into account,whereby more generalized application scenarios with high frequency, large bandwidth or larger aperture length for imaging a target scene located within either the far-field or the near-field of the radar aperture are processable with high accuracy. In addition, convergence acceleration methods in computational mathematics are introduced to accelerate the convergence of the image series expansion, so as to make the algorithm more efficient. The proposed algorithm has been validated both qualitatively and quantitatively with an extensive collection of numerical simulations and field measurements of ground-based SAR(GB-SAR) data set.
作者：
DRAUX, AUNIV LILLE 1
UFR IEEAANAL NUMER & OPTIMISAT LABF-59655 VILLENEUVE DASCQFRANCE
In the case of a non-commutative algebra, the epsilon algorithm is deduced from the Padé approximants at t = 1, and from the use of the cross rule; their algebraic properties are a consequence of those verified b...
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In the case of a non-commutative algebra, the epsilon algorithm is deduced from the Padé approximants at t = 1, and from the use of the cross rule; their algebraic properties are a consequence of those verified by the Padé approximants. The computation of the coefficients is particularly studied. It is shown, that it does not exist any non-invertible needed elements if and only if the Hankel matrices M k (Δ′ S n ) = (Δ′ S n+i+j ) i=j=0 k −1 for l =1, 2 and 3, have an inverse. Some results of convergence and convergence acceleration are also given.
An extrapolation procedure for the evaluation of finite range singular integrals is suggested which is based on the application of the e-algorithm to accelerate sequences of quadrature approximations. These sequences ...
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An extrapolation procedure for the evaluation of finite range singular integrals is suggested which is based on the application of the e-algorithm to accelerate sequences of quadrature approximations. These sequences are produced by integrating over increasingly small sub-intervals using the powerful pseudo-Gaussian quadrature formulae of Patterson. Extensive numerical tests are carried out on a large number of test integrals and critical comparisons made with existing methods.
An improved procedure for numerical inversion of Laplace transforms is proposed based on accelerating the convergence of the Fourier series obtained from the inversion integral using the trapezoidal rule. When the ful...
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An improved procedure for numerical inversion of Laplace transforms is proposed based on accelerating the convergence of the Fourier series obtained from the inversion integral using the trapezoidal rule. When the full complex series is used, at each time-value the epsilon-algorithm computes a .(trigonometric) Padé approximation which gives better results than existing acceleration methods. The quotient-difference algorithm is used to compute the coefficients of the corresponding continued fraction, which is evaluated at each time-value, greatly improving efficiency. The convergence of the continued fraction can in turn be accelerated, leading to a further improvement in accuracy.
The third author discovered numerically an interesting phenomenon that the Aitken acceleration to the ratio pn=fn-1/fn of the successive Fibonacci numbers fn-1 and pn in exactly p2n. This fact has a natural extension ...
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