Antenna array with switching scanning in elevation plane

It is known that the most reliable communication in hard-to-reach places such as the Arctic, Tundra, Taiga is satellite communication [1-5]. Therefore, for satellite communications, it is necessary to develop your own antenna arrays. This article discusses a waveguide-slot antenna array with a Luneburg lens for a mobile satellite communications terminal, which provides a continuous and stable signal. This antenna operates in the 10.9 to 14.5 GHz frequency range. Possesses vertical polarization. The overall dimensions of the antenna array are: diameter of the diagram-forming lens 256 mm (thickness 5 mm, material FLAN 2.8 (epsilon 2.8, tangent delta 0.0015)); waveguide length 600 mm (internal section 10.5 mm by 5 mm, filling FLAN 2.8). Slotted waveguide antennas and lens are made of standard FLAN 2.8 material (epsilon 2.8, tangent delta 0.0015) 5mm thick, foiled on both sides. There are 17 coaxial cables to the HF switch (equal lengths are not required), the scanning step in elevation is 5 degrees. When using 54 waveguide-slot antennas and 18 switch inputs, a scanning sector in elevation of 90 degrees is provided. All the nodes were pre-modeled separately a cylindrical Luneburg lens with suitable waveguides, excited by slits; slotted waveguide antennas; coaxial-waveguide transitions.

SWITCHING SCANNING ANTENNA SYSTEM BASED ON A FLAT LUNEBERG LENS WITH CONCENTRIC RINGS

Антенные системы с возможностью широкоугольного сканирования довольно часто используются в современных системах беспроводной связи и радиолокационных системах гражданского и военного назначения. Особое внимание привлекли Smart-антенны (антенны с коммутируемым лучом и адаптивные антенные системы), а также фазированные антенные решетки (ФАР). В работе рассмотрен вариант построения ФАР с коммутационным сканированием с диаграммообразующей схемой в виде плоской линзы Люнеберга, состоящей из системы концентрических диэлектрических колец, размещенных на подложке из материала Rogers 5880. Исследованы влияние кронштейна крепления для ФАР на диаграмму направленности, уровень излучения, снижение коэффициента направленного действия и уровня сектора сканирования в азимутальной плоскости. Максимальный диаметр ФАР 160 мм, полная высота такой антенны получилась 38 мм. Запитка осуществляется при помощи коаксиальных кабелей с волновым сопротивлением 50 Ом. Диаметр самой линзы Люнеберга был выбран 80 мм; полная высота линзы мм. Подложка имеет толщину мм, склеенная слоем клея толщиной 0.025 мм. Концентрические кольца на этой подложке имеют высоту 0.787 мм. Минимальная ширина концентрического кольца (внешнего) мм (при резке УФ лазером минимальная ширина перегородки между отверстиями равна 0.05 мм). Полосковые трансформаторы расположены на плате из материала Rogers 5880 и имеют толщину равную мм Scanning antennas with wide-angle scanning capabilities are widely used in the areas such as modern wireless communications and military and civilian radars. Among them, lens antennas with switched beams and phased array antennas (PHAR) attracted considerable attention. In this paper, we consider a variant of the construction of switching scanning PHAR with a diagram-forming scheme in the form of a flat Luneberg lens consisting of a system of concentric dielectric rings placed on a substrate made of Rogers 5880 material. We studied the effect of the PHAR mounting bracket on the presence of its influence on the radiation pattern, the radiation level, the decrease in the directional coefficient, and the level of the scanning sector in the azimuth plane. The maximum diameter of the PHAR is 160 mm, the full height of this antenna is 38 mm. The power supply is carried out using coaxial cables with a wave resistance of 50 Ohms. The diameter of the Luneberg lens itself was chosen 80 mm; the full height of the lens is H =0.939 mm. The substrate has a thickness of t =0.127 mm, glued with a layer of glue, 0.025 mm thick. The concentric rings on this substrate are 0.787 mm high. Minimum width of the concentric ring (external) d - W =0.25 mm (when cutting with a UV laser, the minimum width of the partition between the holes is 0.05 mm). Strip transformers are located on the board made of Rogers 5880 material and have a thickness of H =0.939 mm

Designing Multi Beam Receiving and Transmitting Aperture LEO Space Communication Systems

In designing the receiving-transmitting active phased antenna array (APAA) an important problem is an achievement of the level of maximum outcome between the receiving and transmitting channels. In the work, the concept of building multi-beam receiving-transmitting antenna systems based on APAA has been considered. The criteria for selecting the type of emitter for an S-band antenna with the specified parameters have been presented. It has been shown that the use of a turnstile emitter based on the printing technology can reduce the complexity of manufacturing without compromising the technical parameters. In accordance with the requirements for volume of the tasks of APAA being designed the optimal geometric and electric characteristics of the turnstile radiator have been calculated. In designing the radiating apertures of the multi-element APAA the specifics of the dependence of their electric characteristics on the inter-element distance has been taken into consideration. To increase the circular polarization coefficient of the apertures being designed, the method of tearing apart of the radiator with further compensation of the obtained phase using the phase rotators APAA has been implemented. The estimates of the energy characteristics of the multi-element antennas with a given scanning sector for various inter-element distances have been given. To ensure the separation of the receiving and transmitting antennas the recommendations have been presented.