Matrix 4-element sis receiver of the 3mm wavelength range for the RT-22 telescope

The goal of this project is to build a 3 mm SIS multi-beam (matrix) receiver for the 22-m radio telescope of the Crimean Astrophysical observatory. This project was launched in collaboration with Group for Advanced Receiver Development (GARD), Chalmers University (Sweden). The receiver employs compact DSB SIS mixers, designed by GARD for matrix receiver applications (Fig. 1). It shows good stability and provides receiver DSB noise temperature better than 50K in the frequency range 85–110 GHz. Broadband impedance transformation of the SIS junction allows covering working frequency band with a fixed backshort position.