An X-Band Parametric Amplifier with Closed-Cycle Cooling

The objective of the work described here was to develop a system-oriented closed-cycle cooled parametric amplifier using a commercially available cooler. The desired characteristics were: tuning range, 7.0 to 8.0 Gc; instantaneous bandwidth, 20 to 30 megacycles; effective noise temperature, about 70/spl deg/ Kelvin including the uncooled X-Band four port circulator. The compatibility for use, at a later date, of more complex multistage coolers to allow cooling of the circulator and parametric amplifier combination, was also an important consideration.