DEVELOPMENT OF A LARGE DYNAMIC RANGE TUNNEL DIODE AMPLIFIER FOR PHASED ARRAY RECEIVERS

Abstract : The objective of this two phase program is to develop large dynamic range S-band tunnel diode amplifiers for phased array receivers. Phase I calls for the development of a prototype amplifier, and phase II for a reproducibility study of amplifiers and an investigation of amplifier characteristics pertinent to phased array applications. This report covers the theoretical and experimental work performed under phase I of the program. The theoretical considerations show that an optimum combination of low noise and large dynamic range can be realized by cascading two amplifiers. The first stage of this amplifier must provide low noise performance, and the second stage large power output. In the experimental amplifiers developed under this program Ge tunnel diodes were used in the first stage and GaAs tunnel diodes in the second stage. These diodes were mounted in special ultra low inductance stripline packages. One two stage tunnel diode amplifier was delivered to Lincoln Laboratories. This amplifier operates at a center frequency of 2.86Gc, has a 1.5db bandwidth of 120Mc, a gain of 17.3db and a noise figure of 5.6db. The amplifier is unconditionally stable and its output power at the 1db gain compression point is -13.7dbm. (Author)