Синтез и оптимизация посекционного полиномиального Е-импульса при решении задачи различения объектов по собственным резонансам
In this paper, the E-pulse (extinction pulse) method known as aspect-independent ultra-wideband radar target discrimination technique is discussed. An alternative synthesis algorithm for the subsection polynomial E-pulse is introduced. The algorithm consists in building a skeleton E-pulse, its further extending and series of integration which all could be performed over the coefficients of basic functions. Not only the proposed algorithm performs up to a thousand times faster than direct matrix solution but it obtains the polynomial coefficients of the E-pulse sections avoiding the solution of a linear problem associated with ill-conditioned sparse matrix. It is proven that E-pulse signals synthesized by means of the fast algorithm and the direct one are exactly the same. To exposure the features of the E-pulse technique, two targets discriminating scheme has been simulated.
In this paper, E pulse target discrimination method which uses the time-domain target response to a wideband incident waveform is discussed. Based upon the resonant model of the transient behavior of conducting targets obtained and formularized via the singularity-expansion method (SEM), the E pulse method allows developing the computationally efficient technique for discrimination of radar targets. The E pulse is defined as a finite duration waveform, which annihilates a preselected number of the natural resonances of a particular target. Mathematically, this means the convolution product of the target response and the E pulse matched to the target will vanish in late-time part. The E pulse can be analytically represented as a weighted sum of convenient basis functions. The most useful basis set, due to its great simplicity, is one that is composed of subsectional polynomial pulse functions. Finding the coefficients of polynomials to obtain functions that determine the waveform of E pulse over each of the sections could be ob-tained by solving large-scale system of linear equations with elements evaluated sophisticatedly. In practice, there emerges a chain of difficulties associated with this problem, for example, an ill-conditioned matrix case. The purpose of this work is to introduce an alterna-tive synthesis algorithm of polynomial based E pulses. This multistep algorithm proposes producing an E pulse consisting of delta-functions at the first step, and then, a series of step-by-step cross convolutions up to the desired polynomial degree. Not only does this solution not imply solving any equations but it also requires a great deal few operations than standard equation solving procedure. In addition, the discrimination scheme assembled for this method was investigated. The E pulse technique performance was confirmed by numerical simulation using natural resonances of two aircraft scale models: Boeing 707 (B-707) and McDonnel Douglas F-18.
Generalized error-locating codes are discussed. An algorithm for calculation of the upper bound of the probability of erroneous decoding for known code parameters and the input error probability is given. Based on this algorithm, an algorithm for selection of the code parameters for a specified design and input and output error probabilities is constructed. The lower bound of the probability of erroneous decoding is given. Examples of the dependence of the probability of erroneous decoding on the input error probability are given and the behavior of the obtained curves is explained.
The dynamics of a two-component Davydov-Scott (DS) soliton with a small mismatch of the initial location or velocity of the high-frequency (HF) component was investigated within the framework of the Zakharov-type system of two coupled equations for the HF and low-frequency (LF) fields. In this system, the HF field is described by the linear Schrödinger equation with the potential generated by the LF component varying in time and space. The LF component in this system is described by the Korteweg-de Vries equation with a term of quadratic influence of the HF field on the LF field. The frequency of the DS soliton`s component oscillation was found analytically using the balance equation. The perturbed DS soliton was shown to be stable. The analytical results were confirmed by numerical simulations.
Radiation conditions are described for various space regions, radiation-induced effects in spacecraft materials and equipment components are considered and information on theoretical, computational, and experimental methods for studying radiation effects are presented. The peculiarities of radiation effects on nanostructures and some problems related to modeling and radiation testing of such structures are considered.
This volume presents new results in the study and optimization of information transmission models in telecommunication networks using different approaches, mainly based on theiries of queueing systems and queueing networks .
The paper provides a number of proposed draft operational guidelines for technology measurement and includes a number of tentative technology definitions to be used for statistical purposes, principles for identification and classification of potentially growing technology areas, suggestions on the survey strategies and indicators. These are the key components of an internationally harmonized framework for collecting and interpreting technology data that would need to be further developed through a broader consultation process. A summary of definitions of technology already available in OECD manuals and the stocktaking results are provided in the Annex section.