Measurements with an 'Inverted' Mixer Noise Generator at 1200 Megacycles

Abstract

A 1200 megacycle low noise figure receiver was constructed and its noise figure measured by means of a microwave noise generator. The generator consisted of a planar diode from which the available noise power at intermediate frequencies was converted to microwave frequencies by an 'inverted' mixer. The planar diode referred to above was a CV. 172 which, when used in conjunction with the 'inverted' mixer, acted as a standard microwave noise source. The receiver was used as a means of comparing the available noise power from the diode microwave noise generator with that from a gas discharge. The equivalent noise temperature of three fluorescent discharge lamps was measured and the average was found to he 15.8 ± 0.3 db with respect to 290°K.