A new method for high sensitivity noise measurements

A new method for high sensitivity noise measurement, based on the elaboration in the time domain of the signals coming from two identical amplifiers, is presented in this paper. The most important advantage of this method, which in most cases allows one to obtain an equivalent background noise well below (30 dB) that of the amplifiers which are used in the measurement chain, lies in its simplicity and in the fact that it does not depend on the method used for the estimation of the noise spectra. Moreover, although it is best employed using a two channel spectrum analyzer, it can be applied also in the case in which only a single measurement channel is available