  This paper studies the mean square stabilization problem of vector LTI
systems over power constrained lossy channels. The communication channel is
with packet dropouts, additive noises and input power constraints. To overcome
the difficulty of optimally allocating channel resources among different
sub-dynamics, schedulers are designed with time division multiplexing of
channels. An adaptive TDMA (Time Division Multiple Access) scheduler is
proposed first, which is shown to be able to achieve a larger stabilizability
region than the conventional TDMA scheduler, and is optimal under some special
cases. In particular, for two-dimensional systems, an optimal scheduler is
designed, which provides the necessary and sufficient condition for mean square
stabilization.
