Noise - Friend or Foe?

Abstract : In this presentation, it is shown that noise can be not only a source of difficulty in measurement situations, but can also be used as an information carrier. In most situations, noise serves to obscure signals whose detection is desired. In such situations, it is important to distinguish between additive and multiplicative noise. Additive noise can be overcome by means of conventional signal-processing techniques such as lock-in amplification, signal averaging, and others. In contrast, multiplicative noise can be overcome only through a division-based process such as internal standardization. From another viewpoint, noise can serve nicely as distinctive information carrier and as a vehicle by which time-dependent phenomena can be measured. This approach has a number of advantages, including signal-to-noise enhancement and the examination of systems which cannot readily be perturbed by pulsed methods. Correlation, Signal-to-noise enhancement, Stochastic fluorimetry, Linear response theory.