Design Of Decentralized Dynamic Routing Strategy For Traffic Networks

This paper studies the decentralized H∞control for robust dynamic routing in traffic networks with time-varying delay, we assume that the delays in the queuing model are unknown a priori and fast time-varying. By designing a local state feedback controller for each node, the proposed global objective function which is the worst-case queuing length is minimized, that is the decentralized routing problem is formulated as an optimal H∞control problem to achieve a robust routing performance in presence of unknown fast time-varying network delays. Firstly, unconstrained solution is derived to design a decentralized H∞controller and expressed in terms of the feasibility of LMI. Secondly, physical constraints are imposed and expressed as LMIs. Thus the resulting optimization problem is recast as a linear objective minimization problem involving LMI constraints, and a new stability criterion is established in terms of Linear Matrix Inequalities (LMIs), less conservative and less complex. Our proposed decentralized routing scheme not only determines the fastest route in presence of the unknown time-varying delays, but also is scalable to potentially large traffic networks.