8 Elements phased array antenna using superconducting receiving module

We have proposed a 3 GHz band active phased array antenna with a high-sensitivity cryogenic receiving unit. The high-sensitivity cryogenic receiving unit has 8 receiving modules, and each module consists of a small high-Tc superconducting (HTS) filter and a cooled low noise amplifier (LNA). The vacuum chamber size of this cryogenic receiving unit is 152×180×119 mm. As shown in this paper, measured noise temperature of the cryogenic receiving unit cooled at 77 K improved to less than 1/3 as compared with the noise temperature of only LNA at room temperature. Then the active phased array antenna consisted of the high-sensitivity cryogenic receiving unit, array antenna with circular arrayed antenna elements, and combiner unit. The active phased array antenna realized beam scan angle between -45 degree and 45 degree in azimuth. Also measured results were good agreed with calculation results.