High-Frequency Negative-Resistance Circuit Principles for Esaki Diode Applications

Abstract

Certain fundamental principles are presented for analyzing and designing high-frequency amplifiers and oscillators utilizing simple negative resistance elements such as the Esaki or tunnel diodes. The first part of the paper covers the conditions necessary for oscillation and amplification with a single negative-resistance diode, including stability criteria, gain and bandwidth. It is shown that the highest-frequency circuits require diodes with very small dimensions, so that a single-spot diode will have a very low power capacity. In order to obtain higher power at high frequencies, distributed circuits must be used, either with narrow-strip diodes or a multiplicity of small spot diodes. Such circuits present special stabilization problems in suppressing unwanted modes of oscillation. Methods of avoiding such difficulties are presented for one-port oscillator circuits and for traveling-wave amplifier circuits. In the latter case, nonreciprocal attenuation of the gyromagnetic type is recommended.