  This paper deals with the state estimation of linear time-invariant systems
using distributed observers with local sampled-data measurement and aperiodic
communication. Each observer agent perceives partial information of the system
to be observed but does not satisfy the observability condition. Consequently,
distributed observers are designed to exponentially estimate the state of the
system to be observed by time-varying sampling and asynchronous communication.
Additionally, explicit upper bounds on allowable sampling periods for
convergent estimation errors are given. Finally, a numerical example is
provided to demonstrate the validity of the theoretical results
