Spline-Profile Horn for Array Applications in Radio Astronomy

Abstract

In this paper the properties of an optimized compact smooth-walled spline-profile horn for the 30÷38 GHz frequency band is described. The measured 3 dB beamwidths are 40° in the H-plane, 37° in the E-plane, and 38° in the 45°-plane. The measured sidelobe levels are less than –30 dB in H-plane, –23 dB in E-plane, and –25 dB in 45° -plane. The maximum gain is 13.8 dBi. The measured crosspolarization level is less than –20 dB at the top of the band. The antenna measurement and test results are in good agreement with simulation. The results of the trial observations at the RATAN-600 radio telescope with the horn are given. We consider using such a horn as an efficient element in a multi-beam receiving array for a radio telescope.