Optoelectronics, Instrumentation and Data Processing (v.44, #4)

Linear signal distortion compensation using harmonic decomposition by V. M. Efimov; A. L. Reznik; A. V. Torgov (285-292).
Compensating for linear distortions of a signal under uniform sampling using Fourier series is considered.

An algorithm for estimating the parameters of projective transformations and distortion using the Golub-Pereyra method is obtained. The algorithm made it possible to reduce the space of the parameters optimized. Behavior of the objective function was analyzed as the parameters approached singular lines. Results of experiments are presented. The results validate the possibility of using the algorithm for solving the problem of constructing panoramic pictures obtained by usual digital cameras.

Welch-type spectral density estimator. Additional recommendations by V. G. Alekseev; V. A. Sukhodoev (302-305).
The Welch-type spectral density estimator is considered once more. Some practical recommendations that make it possible to facilitate and speed up considerably the calculation of the estimator are formulated.

Using nonstationary season autoregressive integrated moving average models in resource saving problems by R. R. Akhmetyanov; L. A. Delegodina; N. P. Kopylova; B. N. Lutsenko; G. M. Sobstel; G. P. Cheido (306-316).
A technique for identifying and estimating the parameters of a multiplicative autoregressive integrated moving average model is considered. The model is used for describing homogeneous nonstationary processes with season variations. The technique is based on selective sounding the space of model parameters. The approach differs from the one that usually uses correlation and partial correlation functions. It enables working with large-dimension models and a great number of seasons. Forecasting the energy resource consumption is illustrated.

The problem of optimal filtering the signal frequency at the frequency detector output against flicker noises with the power spectral density ω−γ is considered. In a stationary approximation, a simple fractionally rational model of the spectra of frequency finite-power flicker noises is proposed. The optimal impulse response function of the device, which ensures an effective, unbiased, and consistent estimate of the parameter with regard to the edge effects at the ends of the measurement interval and the optimal frequency estimate variance are obtained. Precision of the estimates for different types of noise and device is compared.

Aquasioptimal method for control of antenna arrays in information-measurement systems is considered. The method is based on optimizing the form of directivity pattern of an array under complex amplitude current control in some of its elements. The advantage of the method is high-speed operation as a result of reducing expenses on calculating optimal parameters of the antenna system.

Controlled classification of Earth remote sensing data by V. V. Asmus; A. A. Buchnev; V. P. Pyatkin (331-336).
A system of controlled classifying (trainable) the Earth remote sensing data is described. Computational experiments for estimating the distributed data processing efficiency are presented.

Obtaining the estimates of time position of pulse signals caused by human steps and detected by a seismic observation system is considered. The sequence of pulse appearance moments is described by the Markovian process. The estimates are obtained using nonlinear Markovian filtering. A method for fast calculating a one-step likelihood function without using its approximation is proposed. Statistical modeling results of experimental investigating the synthesized algorithm are presented.

Diffractive-refractive intraocular lenses by G. A. Lenkova; V. P. Korolkov; V. P. Koronkevich; R. K. Nasyrov; A. S. Gutman; I. A. Iskakov; V. M. Treushnikov (342-352).
Optical characteristics and properties of AcrySof ReSTOR® bifocal intraocular lenses (Alcon, USA) and elastic polymer MIOL-Akkord lenses (Russia) are compared. The lenses differ by the form of refractive component, the type of diffractive microstructure, and their fabrication technology. Investigations showed that the lenses have similar optical characteristics in resolution, but the bifocal properties of the MIOL-Akkord are much less dependent on the pupil diameter.

On the model of binocular visual space by A. M. Kovalev (353-360).
A quadratic fractional function of mapping the Euclidean space onto the interior of a sphere of the Klein model of the Lobachevsky space is proposed. The mapping considers the horizontal empirical horopter as a peculiarity of binocular vision. Theoretical and experimental data are compared. Effects of inverse perspective and superconstancy of object sizes are illustrated.

An afocal optical system for correcting refraction anomalies of eye by G. A. Lenkova; P. S. Zavyalov (361-365).
Results of designing and analyzing the optical device for continuous correction of refraction anomalies of eye (myopia or hypermetropia). It is proposed to build the device into a system intended for objective measuring the optical characteristics of eyes.

A method for designing refractive-diffractive spectacle glasses using differential formulas for calculating narrow beams passing through a diffractive optical element is developed. Glasses with a high positive dioptric power are analyzed and their aberrations are compared with those of refractive spectacle glasses.

Wavefront sensors for adaptive optical systems by V. P. Lukin; N. N. Botygina; O. N. Emaleev; P. A. Konyaev (377-383).
Possibilities of constructing a wavefront sensor for the adaptive system in the Big Solar Vacuum Telescope are considered. A modified correlation tracker (MCT) is proposed. The sensor is tested by measuring the displacement of the image of the solar granulation pattern in the first and second foci of the telescope under clear vision conditions. The change in the quality of the image being transferred to the second focus and the measured displacement of the image of solar granulation in the second focus with extremely good vision conditions and a certain granulation structure are analyzed. The effect of reduction of the input aperture to 170 mmon the image quality and, hence, on MCT operation is analyzed.