Title :
Design and Characterization of a 211–275 GHz Sideband Separating Mixer for the APEX Telescope
Author :
Vassilev, V. ; Henke, D. ; Lapkin, I. ; Nyström, O. ; Monje, R. ; Pavolotsky, A. ; Belitsky, V.
Author_Institution :
Dept. of Radio & Space Sci., Chalmers Univ. of Technol., Goteborg, Sweden
Abstract :
We present the final results of the development and characterization of the sideband separating superconductor-insulator-superconductor (SIS) mixer for the APEX telescope band 1 (211-275 GHz). The sideband separation is achieved by using a quadrature scheme where the radio frequency (RF) and a local oscillator (LO) power are applied to two identical double sideband SIS mixers. All mixer components, including the LO and RF distribution circuitry, are integrated into a single mixer block. To achieve a compact design we developed a superconducting Lange coupler, based on Nb thin film, which is used as an intermediate frequency hybrid. Typical single sideband noise temperature of 100 K and sideband rejection ratio of about 12 dB and are measured.
Keywords :
millimetre wave mixers; radiofrequency oscillators; radiotelescopes; superconducting microwave devices; superconductor-insulator-superconductor mixers; APEX telescope; double sideband SIS mixers; frequency 211 GHz to 275 GHz; local oscillator power; quadrature scheme; radio frequency; sideband separating mixer characterization; sideband separating mixer design; single sideband noise temperature; superconducting Lange coupler; superconductor-insulator-superconductor mixers; Coupling circuits; Local oscillators; Niobium; Optical design; Radio frequency; Superconducting device noise; Superconducting devices; Superconducting thin films; Telescopes; Thin film circuits; Quadrature hybrid; sideband separating mixers; superconductor–insulator–superconductor (SIS) mixer;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2007.912026
