Optimization and Systems Theory Seminar
Tuesday, November 27 2007, 10.00-11.00, Room 3721, Lindstedtsvägen 25

Ling Shi, Caltech, USA
E-mail: shiling@cds.caltech.edu

State Estimation and Energy Optimization Over Multi-hop Sensor Networks

New control paradigms are needed for large networks of wireless sensors and actuators in order to efficiently utilize system resources. In this talk we consider when state estimation is carried over a sensor network. A fusion center forms a local multi-hop tree of sensors and fuse the data into a state estimate. It is shown that the optimal estimator over a sensor tree is given by a Kalman filter of certain structure. The number of hops that the sensors use to communicate data with the fusion center is optimized such that either the overall transmission energy is minimized or the network lifetime is maximized. In both cases the fusion center provides a specified level of estimation accuracy. A heuristic algorithm is presented that leads to a suboptimal solution and has low computational complexity in the energy minimization problem, while an algorithm that leads to the global optimal solution is proposed in the lifetime maximization problem.

Bib: Ling Shi received the B.S. degree in Electrical and Electronic Engineering from Hong Kong University of Science and Technology in 2002. He is currently a Ph.D student in Control & Dynamical Systems at California Institute of Technology and is expected to receive his Ph.D in Spring 2008. His research interests include networked control systems, wireless sensor networks and distributed control. He has served as program chair and co-chair at various conferences including American Control Conference, IEEE Conference on Decision and Control, etc. He is also an organizer of an invited session in International Federation of Automatic Control 2008 at Seoul, Korea. He has been an active reviewer for IEEE Transactions of Automatic Control, Automatica, etc.
Calendar of seminars Last update: November 19, 2007 by Marie Lundin.