Plasmonic Nanobar-on-Mirror Antenna with Giant Local Chirality: a New Platform for Ultrafast Chiral Single-Photon Emission

Providing an additional degree of freedom for binary information encoding and nonreciprocal information transmission, chiral single photons have become a new research frontier in quantum optics. Without using complex external...

METHOD FOR CALCULATING A TWO-MIRROR ANTENNA OF THE GREGORY TYPE

Предложен способ расчета двухзеркальной антенны Грегори, отличающийся введением виртуального дополнительного облучателя для повышения точности расчетов шумовой температуры. Приведен пример расчета антенны. A method for calculating a two-mirror Gregory antenna is proposed. The method is characterized by the introduction of a virtual additional irradiator to increase the accuracy of noise temperature calculations. An example of the antenna calculation is given.

Two-mirror cylindrical antenna system with high efficiency.

A technique for the synthesis of two-mirror cylindrical antenna systems for a given amplitude distribution in the aperture has been developed. At the first stage geometrical-optical synthesis is carried out, at the second stage a refined solution is found using the field of the feed on the secondary mirror found by the numerical method of finite element. As an example, a two-mirror cylindrical antenna system with a horn-lens feed and a uniform field distribution in the main mirror aperture has been synthesized. Using full-wave simulation by the finite element method, the analysis of the radiation characteristics of a synthesized two-mirror antenna system is carried out. The scanning characteristics of the antenna system by turning the main mirror are investigated. The efficiency of a cylindrical two-mirror antenna system with a horn-lens waveguide transition in the E-plane and an H- sectorial horn feed reaches 0.95 i.e. is close to the limiting value. When scanning the main lobe of the pattern in an angular sector of 27 degrees due to the rotation of the main mirror gain exceeds 26 dB, and efficiency exceeds 0.8.

DIGITAL LOAD MODELS OF PRECISION MIRROR ANTENNA FOR INTELLIGENT SUPPORT OF THE OPERATION STAGE

Рассматриваются условия нагружения зеркальных антенн воздушным потоком и тепловыми воздействиями с учетом вариабельности пространственного положения конструкции. Предложена концепция построения цифровых моделей нагруженности крупногабаритной прецизионной антенны наземных систем спутниковой связи. Определены возможности их интеграции в контуры принятия решений для интеллектуальной поддержки стадии эксплуатации. The conditions for loading reflector antennas with air flow and thermal effects are considered, taking into account the variability of the spatial position of the structure. A concept is proposed for constructing digital models of the loading of a large-sized precision antenna for ground-based satellite communication systems. Possibilities of their integration into decision-making contours for intelligent support of the operation stage have been determined.

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.

Analysis of Current State and Prospects for Development of Methods for Monitoring Tension of Radio-Reflecting Mesh on Deployable Frame of Large Mirror Antenna

The article considers the problems of developing an operating automated method for monitoring the force and uniformity of tension of a radio-reflecting mesh on the deployable frame of large mirror antennas. Based on the performed analysis of known control methods they are classified as contact mechanical methods and non-contact optical ones. It is shown that only optical monitoring methods provide automated control of the tension force of the radio-reflecting mesh on the frame. Among the known optical methods for monitoring, only the moire band method allows creating an immediate picture of the uniformity of the tension of the radio-reflecting mesh over the entire surface under consideration. The method is based on the revealed relationship of moire patterns with the uniformity and tension force of the radio-reflecting mesh. The advantages of the described method are shown; the main advantage is the possibility of installing a radio-reflecting mesh on the deployable frame of the large mirror antenna in real time. Due to its versatility, the proposed method can be used in any other structures where the element being tested is a grid, regardless of the material from which it is made.