4-gc Parametric Amplifier for Satellite Communication Ground Station Receiver

High sensitivity, stability and reliability are important requirements for a satellite communication ground station receiver. The maser has come to be considered the ideal preamplifier for satellite communication due to its superlative low-noise performance, and it is indeed ideal for cases where its cost and maintenance requirements are not of major concern. However, for lighter traffic routes where cheaper terminals are required, it is desirable to have a less expensive, more compact, and more easily maintained microwave preamplifier. This has motivated the development of the variable capacitance parametric amplifier described in this paper. A block diagram of the parametric receiver is shown in Fig. 1. The receiver consists of four major sections: a circulator type parametric amplifier, an extremely stable 23-gc pump source, an efficient cryogenic system, and a control system. The first-stage amplifier is operated at liquid nitrogen temperature. The varactor diode mount, circulator, 1SS7