Electromagnetic Model of Dual Reflector Radio Telescope based on Laser Scanning Survey

In this paper model based on laser scanning survey of Ventspils International Radio Astronomy Centre (VIRAC) 32-m dual reflector radio telescope RT-32 is investigated using electromagnetic simulation. High density point cloud which simultaneously includes the main and sub-reflectors allows to generate triangular mesh suitable for physical optics simulation for estimation of the focal point, optimum feed edge taper, far field beam patterns, and aperture errors with limited knowledge of the actual theoretical shape of the reflectors which is the case of RT-32 antenna. Analysis is carried on laser scanning data sets obtained at elevations of 90°, 36° and 6° allowing the assessment of gravitational influence on aperture shape. Obtained results such as beam patterns and aperture efficiency are comparable to those obtained experimentally allowing to conclude that described method is useful in case of large reflector antenna systems operating at centimetre wavelengths.