Distributed filtering for uncertain systems under switching sensor networks and quantized communications

This paper considers the distributed filtering problem for a class of stochastic uncertain systems under quantized data flowing over switching sensor networks. Employing the biased noisy observations of the local sensor and interval-quantized messages from neighboring sensors successively, an extended state based distributed Kalman filter (DKF) is proposed for simultaneously estimating both system state and uncertain dynamics. To alleviate the effect of observation biases, an event-triggered update based DKF is presented with a tighter mean square error (MSE) bound than that of the time-driven one by designing a proper threshold. Both the two DKFs are shown to provide the upper bounds of MSE online for each sensor. Under mild conditions on systems and networks, the MSE boundedness and asymptotic unbiasedness for the proposed two DKFs are proved. Finally, numerical simulations demonstrate the effectiveness of the developed filters. (C) 2020 Elsevier Ltd. All rights reserved.