Theoretical Proving of Optimal Communication Radius Against Traffic Congestion in Simplified

Different from the traditional traffic network, the connected vehicles enable information exchange with each other in vicinity, resulting in potentially reshaping the propagation process of traffic congestion from the perspective of a widespread spatial correlation. The communication radius as the determinant in interconnecting vehicles undoubtedly should be optimally adjusted to maximize the utility in a varying context. The communication radius heavily determines the perception range of traffic information, and accordingly affects traffic congestion evolution. Intuitively, the length of communication radius poses positive effects on the mitigation of traffic congestion due to the enlarged range of exchanged traffic information. This paper aims to model the traffic-congestion evolution in a simplified abstraction of connected vehicles, and especially focuses on investigating the effects of communication radius on the traffic congestion. We theoretically formulate the relation between the communication radius and the traffic congestion in a lattice space, and then prove the optimal value of traffic congestion available against the communication radius. Both the numerical analysis and simulation results show that the connected vehicles can effectively improve the traffic congestion, however, the incremental enlargement of the communication radius fails to relieve traffic congestion further as the originally envisioned if already reaching to an optimal value that we theoretically deduce in this work.