Superconducting low noise receivers

It is now possible to develop a new class of receivers for the millimeter and shorter wavelength region by application of Josephson and other electron tunneling phenomena which occur in superconducting materials. This development represents a major advance in receiver sensitivity and will be applicable over a wide frequency interval. Operating in the conventional heterodyne detection mode this receiver has a theoretical noise temperature as low as 20 Kelvin at 100 GHz. Three basic components required are: a superconductor-semiconductor Schottky diode mixer; a Josephson junction phase-locked multiplier local oscillator; and a Josephson parametric amplifier. The component and system design and limiting factors will be discussed.