Asymptotically Optimal Quickest Change Detection in Distributed Sensor Systems

Abstract

Abstract: In the standard formulation of the quickest change-point detection problem, a sequence of observations, whose distribution changes at some unknown point in time, is available to a decision maker, and the goal is to detect this change as quickly as possible, subject to false alarm constraints. In this paper, we study the quickest change detection problem in the setting where the information available for decision-making is distributed across a set of geographically separated sensors, and only a compressed version of observations in sensors may be used for final decision-making due to communication bandwidth constraints. We consider the minimax, uniform, and Bayesian versions of the optimization problem, and we present asymptotically optimal decentralized quickest change detection procedures for two scenarios. In the first scenario, the sensors send quantized versions of their observations to a fusion center where the change detection is performed based on all the sensor messages. In the second scenario, the sensors perform local change detection and send their final decisions to the fusion center for combining. We show that our decentralized procedures for the latter scenario have the same first-order asymptotic performance as the corresponding centralized procedures that have access to all of the