Spectral analysis of signals exhibiting nonstationary stochastic time-shifts

Signals generated or processed by physical systems are often subject to nonstationary stochastic time-shifts. This effect, also known as phase noise, has traditionally been analyzed using mathematical techniques applicable only to stationary processes. In this letter, we present a spectral analysis of signals experiencing stochastic time-shifts, with the fundamental assumption that the ratio between time-shift and time vanishes as time tends to infinity.