80-dB microwave noise from an avalanche transistor circuit

Abstract

Extremely high ‘excess noise ratio’ of 80 dB is observed from an avalanche transistor circuit, operating in a random pulse mode. Broadband noise spectrum measured from 30 MHz to 1 GHz exhibits good flatness with the nonuniformity of only ± 1 dB. Experiments have been performed with the silicon bipolar junction microwave transistors. An analog circuit model is proposed and investigated.