129 GHz SIS MIXER RECEIVER FOR KOREAN VLBI NETWORK
한국우주전파관측망 129 GHz 초전도 믹서 수신기

Jung-Won Lee, Ming-Jye Wang, Chao-Te Li, Tse-Jun Chen, Soo-Yeon Kim, Wei-Chun Lu, Yong-Woo Kang, Sheng-Cai Shi, Seog-Tae Han
2012 Publications of The Korean Astronomical Society  
We have developed superconducting mixer receivers for 129 GHz VLBI observation in Korean VLBI Network (KVN). The developed mixer has a radial waveguide probe with simple transmission line L-C transformer as a tuning circuit to its 5 series-connected junctions, which can have 125 -165 GHz as the operation radio frequency (RF). For intermediate frequency (IF) signal path a high impedance quarter-wavelength line connects the probe to one end of symmetric RF chokes. The double side band (DSB)
more » ... de band (DSB) receiver noise of the mixer was about 40 K over 4 -6 GHz IF band, whereas we achieved the uncorrected single side band (SSB) noise temperature of about 70 K and better than 10 dB image rejection ratio in 2SB configuration with 8 -10 GHz IF band. Insert-type receiver cartridges employing the mixers have been under commission for KVN stations.
doi:10.5303/pkas.2012.27.3.071 fatcat:rkxrb5fi7jaatnqyi5i7dcfjsa