BEAMFORMING UNIT FOR SUB-ARRAY OF DECAMETER AND METER WAVE RADIO TELESCOPE GURT

Abstract

A beamforming device for a 5×5-element subarray of receiving phased antenna array of new GURT radio telescope designed to operate within 10 − 70 MHz is presented. The device is composed of six identical units. Each unit contains equal-arm 5:1 combiner with connected to its arms discrete phase shifters based on time delay lines switching principle. Five of these units combine the signals of array elements inside rows of the subarray, whereas the sixth one assembles the combined signals of subarray rows. Operation principle of beamforming unit is described, the results of its computer modeling and performance measurement results are given. The time-delay lines manufacturing errors influence on subarray power parameters is estimated, as well as their fabrication tolerance found.

Keywords

• phase changer
• beamformer
• phased array
• radio-telescope