| Popis: |
A receiver with an rf band of 34.6 GHz to 35.4 GHz, an integral local oscillator with a frequency of 36.5 GHz, and an IF frequency of 1.1 GHz to 1.9 GHz was designed and fabricated. The rf filter was a three pole distributed design fabricated with High Temperature Superconductor (HTS) films. The IF filter was a 9 pole lumped element design fabricated with HTS films. The local oscillator was a parallel feedback type design using a sapphire resonator shielded by two HTS ground planes. The rest of the elements used normal conductors or semiconductors operated at 77 K. The entire subassembly was integrated into a liquid nitrogen dewar and its performance is reported in the text, with the important figures of merit being low noise figure and low phase noise. |
