Antenna array of waveguide elements with dielectric phasing sections

Abstract

Background. The need to develop and continuously improve mobile and on–board high-speed satellite communication terminals, as well as satellite communication equipment with high secrecy of operation, emitting ultra-wideband signals, the spectral power density of which, measured at the input of receiving devices of radio monitoring complexes, should be significantly lower than the spectral power density of noise, is due to the following circumstances: ensuring reliable and high-quality communication military and civilian users; the development of the domestic element and technological base, import substitution; the need for rescue services in small-sized information transmission and reception systems; the need to develop satellite control systems for military and civilian equipment; the development of precision agriculture programs. An antenna array made of waveguide elements with dielectric phasing sections can serve as one such example. Aim. The model of the antenna element is considered, and its main characteristics are also given. A model of a linear antenna array consisting of 32 waveguide elements with phasing sections has been developed. Linear and flat antenna arrays based on a common-mode and equal-amplitude 1:32 power divider and antenna elements are considered. A model of a flat antenna array composed of 16 linear antenna arrays is also constructed and its main characteristics are given. Methods. The antenna element model is based on a circular waveguide with an internal diameter of 18 mm and a dielectric plate, the plane of which is oriented at an angle of 45° to the lines of force of the electric field intensity vector. The linear antenna array is powered by an equal amplitude and common-mode power divider, and the linear and flat antenna arrays are based on square waveguides with internal dimensions of 14×14 mm2 with beveled internal corners. Results. It is shown that the gain at a frequency of 10,95 GHz is 32,5 dB (normal) and 31,2 dB when the beam is deflected by ±37,5° in the angular plane. The gain at a frequency of 11,7 GHz is 33,8 dB (normal) and 32,5 dB when the beam is deflected by ±37,5° in the angular plane. With the maximum deviation of the main lobe from the normal, the level of the side lobes in the vertical increases to the level of -11,4 dB, which slightly exceeds the UBL with in-phase and equal amplitude field distribution in the headlight aperture (-13,2 dB). Conclusion. In the considered headlight design, the positioning of the main lobe of the radiation pattern in the azimuthal plane is carried out by mechanical rotation of the antenna system. The rejection of two–coordinate electronic scanning was chosen based on considerations of reducing phase shifters (or high-frequency switches) and reducing the cost of headlights.

Keywords

• mobile and airborne satellite communications
• linear antenna arrays
• round waveguides