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Title: Optimal Quickest Change Detection in Sensor Networks Using Ordered Transmissions
Quickest change detection in a sensor network is considered where each sensor observes a sequence of random variables and transmits its local information on the observations to a fusion center. At an unknown point in time, the distribution of the observations at all sensors changes. The objective is to detect the change in distribution as soon as possible, subject to a false alarm constraint. We consider minimax formulations for this problem and propose a new approach where transmissions are ordered and halted when sufficient information is accumulated at the fusion center. We show that the proposed approach can achieve the optimal performance equivalent to the centralized cumulative sum (CUSUM) algorithm while requiring fewer sensor transmissions. Numerical results for a shift in mean of independent and identically distributed Gaussian observations show significant communication savings for the case where the change seldom occurs which is frequently true in many important applications.  more » « less
Award ID(s):
1744129
NSF-PAR ID:
10276702
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
2020 IEEE 21st International Workshop on Signal Processing Advances in Wireless Communications (SPAWC)
Page Range / eLocation ID:
1 to 5
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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