HYBRID MODELUNG FOR ELECTRODYNAMIC ANALYSIS OF LARGE-SIZED OBJECTS

Рассматриваются методы моделирования сложных электродинамических структур, которые состоят из антенны и объекта-носителя, размеры которого превышают 100 длин волн. При выполнении моделирования предлагается рассчитывать характеристики антенны с использованием метода конечного интегрирования, а при установке на платформу-носитель - с использованием метода геометрической дифракции и физической оптики. Развитие современных вычислительных сред позволилo реализовать систему гибридного моделирования, которая позволяет достичь высокой производительности, автоматизации и точности результатов полученного моделирования. При выполнении исследования изучалась ситуация с установкой антенны спутникового позиционирования на подводной лодке, причем размеры носителя антенны превышали 800 длин волн, что делало невозможным применение метода конечного интегрирования для решения задачи. Pассматривается три способа решения поставленной задачи: с использованием диаграммы направленности и ее ручным переносом на место планируемой установки антенны, однонаправленного метода гибридного моделирования с применением источника ближнего поля, гибридного моделирования с обратной связью между проектами. Получено, что наибольшую точность обеспечивает метод гибридного моделирования с обратной связью, однако его применение требует высокой скорости накопителя данных, а также занимает длительное время. Самым скоростным методом является метод гибридного моделирования с однонаправленной связью, так как обеспечиваются автоматизированный расчет и решение поставленной задачи The article discusses methods for modeling complex electrodynamic structures, which consist of an antenna and a carrier object whose dimensions exceed 100 wavelengths. When performing the simulation, we propose to calculate the characteristics of the antenna using the finite integration method and installed on the carrier platform using the method of geometric diffraction and physical optics. The development of modern computing environments has made it possible to implement a hybrid simulation system, which allows achieving high performance, automation, and accuracy of the results of the simulation. When performing the study, we studied the situation with the installation of a satellite positioning antenna on a submarine, and the dimensions of the antenna carrier exceeded 800 wavelengths, which made it impossible to use the finite integration method to solve the problem. The paper considers three ways to solve the problem posed: using the radiation pattern and its manual transfer to the site of the planned antenna installation, unidirectional hybrid modeling method using a near-field source, hybrid modeling with feedback between projects. We found that the highest accuracy is provided by the method of hybrid simulation with feedback, but its application requires a high speed of the data accumulator, and also takes a long time. The fastest method is the method of hybrid modeling with unidirectional communication, as it provides an automated calculation and solution of the problem

Solving problems of radiation and diffraction electromagnetic waves based on integral representations electromagnetic field

Annotation Various forms of integral representations of the electromagnetic field are considered. It is shown that the use of analytically developed integral representations of the electromagnetic field instead of the vector potential method makes it possible to significantly simplify the formulation of the internal and external electrodynamic problem for specific structures. The numerical results of solving problems of radiation and diffraction of electromagnetic waves are presented. It is shown that taking into account the peculiarities of the geometry and using projection functions close to the eigenfunctions of the integral operator of the internal electrodynamic problem for basic elements make it possible to construct effective algorithms for the electrodynamic analysis of metastructures. A mathematical model of a multistage chiral frame is proposed. By the example of a tubular vibrator, the possibility of approximating the solution of an internal electrodynamic problem using eigenfunctions is demonstrated. The prospects for further development of the integral representations of the electromagnetic field method are considered.

Electrodynamic analysis of mirror antennas in the approximation of the barycentric method

In the article, the features of using the barycentric method in solving problems of electrodynamic analysis of mirror antennas are considered. The solution of the internal problem of electrodynamics is the basis of the study. The problem of electrodynamic analysis of a mirror antenna is formulated in the classical representation of the problem of diffraction of an electromagnetic wave on a system of infinitely thin perfectly conducting screens of arbitrary shape and reduced to a system of integro-differential equations. The solution of the latter is performed numerically in the projection formulation of the Galerkin method when determining the approximation of the desired surface current density function in the system of global basis functions formed in the approximation of the barycentric method for the analyzed screen. The integral representation of the electromagnetic field of the mirror antenna, taking into account the properties of the introduced basic functions, is given. Thefeatures of the algorithmic implementation of the developed solutions are clarified. The efficiency and comparative preference of the use of the barycentric method in the problems of electrodynamic analysis of mirror antennas are tested on test examples.