Бортовая антенная решетка для высокоскоростной радиолинии перспективных космических аппаратов

Постановка проблемы. Радиолиния передачи целевой информации (РЛЦИ) является одной из бортовых систем, применяющаяся на всех типах космических аппаратов (КА). В настоящее время к ней предъявляются достаточно жесткие требования в связи с повышением скорости и информационной емкости каналов радиолинии для перспективных КА. Цель. Определить направления развития многоэлементных антенных систем бортовой радиолинии передачи целевой информации, обеспечивающей энергетические и частотные характеристики ВРЛ, а также систематизировать технические решения, удовлетворяющие требованиям к размещению и эксплуатации антенны на борту КА. Результаты. Рассмотрена бортовая антенная система РЛЦИ. Представлены результаты численного моделирования одиночного излучателя, для которого определены частотные и поляризационные характеристики. Приведены характеристики направленности антенной решетки. Разработаны модели волноводных излучателей с комбинированной замедляющей структурой. Проведен анализ характеристик направленности и поляризационных характеристик антенной решетки из волноводных излучателей с комбинированной замедляющей структурой. Практическая значимость. Показано, что антенная решетка обеспечивает требуемый сектор покрытия наземных пунктов приема информации.

The target information transmission radio line is used both as part of large spacecraft and as part of small spacecraft of any purpose. In this article, the on-board antenna system of the target information transmission radio line has been considered. A stepped polarizer is selected as the radiator, which is usually built on the basis of standard waveguides. At the initial stage of development, the WR-112 waveguide was selected as the basis. In the course of working, the electrodynamic modeling of a polarizer with a linear partition and waveguide excitation was performed, during which the following parameters were estimated: the standing wave coefficient, the directional pattern and the dependence of the elliptic coefficient on the angular coordinate in the azimuthal plane. Then an electrodynamic simulation of a coaxial-excited waveguide radiator with a partition was performed, during which the following parameters were estimated: the standing wave coefficient, the directional pattern and the dependence of the elliptic coefficient on the angular coordinate in the azimuthal plane. Further, an electrodynamic simulation of a coaxial-excited waveguide radiator with a stepped partition was performed, during which the following parameters were estimated: the standing wave coefficient, the directional pattern and the dependence of the elliptic coefficient on the angular coordinate in the azimuthal plane. The considered waveguide radiators have the required directional characteristics and frequency characteristics, but their common disadvantage is a relatively large length, which makes it difficult to use them as on-board antennas for small spacecraft. Therefore, there is a need to minimize the longitudinal dimensions of the antenna, whereby an option of using a radiator with a combined decelerating system in the form of a linear or stepped partition and two projections with an exponential envelope is proposed. Electrodynamic modeling of such a radiator has been performed, the standing wave coefficient, the directional pattern, the directional action coefficient and the elliptic coefficient from the azimuthal angular coordinate have been estimated. Thus, the design of a waveguide radiator with a combined retarding system has been developed, which allows reducing its length by half compared to similar radiators on a square waveguide with a linear or stepped metal retarding system. It has been shown that for the same length, a stepped partition provides better matching in the operating frequencies than a linear one. The polarization characteristics and directivity characteristics for a radiator with a linear and a stepped partition have been determined. It has been shown that the elliptic coefficient exceeds 0.7 in the sector of angles (-70°,70°) in the azimuthal plane. The polarization characteristics meet the requirements for on-board satellite communication antenna systems. On the basis of such a radiator, an electrodynamic simulation of a waveguide antenna array of eight elements with a linear partition and protrusions was performed. The standing wave coefficient, spatial directional patterns of the antenna array of waveguide radiators with a linear partition and the dependence of the elliptic coefficient on the angular coordinate in the azimuthal plane are obtained and estimated.