A Single-Chip Dual-Band Switched SIS Mixer

摘要

We investigate a new concept, where a single superconductor-insulator-superconductor (SIS) based mixer chip is switched between two RF frequency bands. A single broadband antenna is used to couple the RF/LO signal to two SIS mixers via a power splitter and two superconducting on/off switches, forming a switching circuit. The planar on/off switches comprise a superconducting microstrip bridging two transmission lines used to alternate the RF/LO signal between the two branches of the power splitter circuit by switching the impedance of the microstrip from the superconducting to normal state, and vice versa. An important application of this dual-band design is to enable combination of adjacent observing astronomical windows into a single receiver cartridge, freeing valuable space in the receiver cabin.