Houdre, ChristianKedem, BenjaminWe provide a necessary and sufficient condition for the almost sure convergence and the strong consistency of the sample autocovariance of a discrete spectrum weakly stationary process. This also clarifies the estimation of the autocovariance function of a mixed spectrum weakly stationary processes.en-USmixed spectrum SLINstationarysample covariancealmost sureamplitudephasezero-crossing rateCommunicationSignal Processing SystemsTechnical Report