Optimal Energy-Efficient Regular Delivery of Packets in Cyber-Physical Systems

LANGUAGE
English
SOURCE
IEEE ICC
Published Date:2015-6
ABSTRACT
In cyber-physical systems such as in-vehicle wireless
sensor networks, a large number of sensor nodes continually
generate measurements that should be received by other nodes
such as actuators in a regular fashion. Meanwhile, energyefficiency
is also important in wireless sensor networks. Motivated
by these, we develop scheduling policies which are energy
efficient and simultaneously maintain “regular” deliveries of
packets. A tradeoff parameter is introduced to balance these
two conflicting objectives. We employ a Markov Decision Process
(MDP) model where the state of each client is the time-sincelast-
delivery of its packet, and reduce it into an equivalent finitestate
MDP problem. Although this equivalent problem can be
solved by standard dynamic programming techniques, it suffers
from a high-computational complexity. Thus we further pose the
problem as a restless multi-armed bandit problem and employ
the low-complexity Whittle Index policy. It is shown that this
problem is indexable and the Whittle indexes are derived. Also,
we prove the Whittle Index policy is asymptotically optimal and
validate its optimality via extensive simulations.