For decentralized control problems with quadratically invariant information constraints, the optimal controller may be found efficiently. In this paper, we show that there are systems which are not quadratically invariant but reduce to systems that are. We call the requisite property internal quadratic invariance. We present an associated reduction procedure, and illustrate our method with examples.
['Laurent Lessard', 'Sanjay Lall']
Reduction of decentralized control problems to tractable representations