Event-based distributed state estimation under deception attack

Recently, security issues in wireless sensor networks (WSNs) have attracted lots of attention. It is necessary to design effective measures against the attacker. In this paper, a novel distributed state estimator with an event-triggered scheme is proposed to defend against false data injection attack in WSNs. Here, each sensor detects the rightness of its estimate according to a condition at each time step. When the condition is satisfied, the sensor regards it is not attacked, then it is triggered to send the estimate to its neighboring sensors; Otherwise, the sensor is not triggered. Based on the event-triggered scheme, an optimal estimator gain is designed by minimizing the mean-squared estimation error covariance, and then a sufficient condition is provided to guarantee the stability of the proposed distributed estimator. Finally, a numerical example is provided to illustrate the effectiveness of the proposed estimator with event-based strategy.