  A networked output feedback loop subject to packetized transmissions of the
output signal is considered. Based on the small gain theorem, an easy-to-use
stability criterion covering two important cases is presented. In the first
case a packet numbering mechanism is employed whereas in the second case
neither packet numbering nor synchronization between sender and receiver is
assumed. The analysis makes use of acausal subsystems and deduces the optimal
constant time delay that should be used in a nominal controller design such
that additional packet delay variations introduced by the network are
maximized. A simulation example of a networked control system with a filtered
Smith predictor illustrates the application of the proposed criterion and
compares the results to different approaches from literature.
