Online distributed network traffic signal control using the cell transmission model

This paper considers the solution of the adaptive network traffic signal control problem under a fully distributed architecture. To achieve a system-wide optimal solution, the problem is modeled as a large-scale mixed integer linear program with the traffic dynamics being captured by the cell transmission model. To achieve an online distributed solution to the considered problem, the loosely connected structure of transportation networks is exploited to decompose the problem in both space and time. The proposed solution methodology involves two main phases. In the first phase, binary decision variables are relaxed and the resulting linear program is distributedly solved via the alternating direction method of multipliers. The second phase involves distributed rounding of the obtained relaxed solution. Simulation results demonstrate the effectiveness of the proposed approach in providing close to optimal, online solutions.