Decentralized signal control for urban road networks

Abstract

We propose in this paper a decentralized traffic signal control policy for urban road networks. Our policy is an adaptation of a so-called BackPressure scheme which has been widely recognized in data network as an optimal throughput control policy. We have formally proved that our proposed BackPressure scheme, with fixed cycle time and cyclic phases, stabilizes the network for any feasible traffic demands. Simulation has been conducted to compare our BackPressure policy against other existing distributed control policies in various traffic and network scenarios. Numerical results suggest that the proposed policy can surpass other policies both in terms of network throughput and congestion.

Traffic signal control and route choice: A new assignment and control model which designs signal timings

“…There has recently been a sharp increase in interest in local distributed traffic signal control policies which are queue stabilising; see for example Varaiya (2013) and Le et al (2013). In almost all of this work so far re-routeing by travellers is not substantially considered; and the relationship between these policies and P 0 are of interest.…”

“…All three policies work in a very broadly similar way (seeking to equalise certain stage pressures). The Varaiya (2013) and the Le et al (2013) pressures are written in terms of queues whereas P 0 pressure is given in terms of bottleneck delays. To compare these pressures it is natural to use a formula connecting the queue volume Q i , the bottleneck delay b i and the green-time g i on a link.…”

“…One such function is: b i ¼ Q i =g i s i . The main difference between the three policies is that Varaiya (2013) and Le et al (2013) have backpressure while P 0 does not. This is then one area of possible future study: perhaps adding the natural backpressure to P 0 will yield a policy which is not only capacity maximising but also queue stabilising.…”

“…Finally it is natural to consider studying connections between the distributed control policies designed by Varaiya (2013) and Le et al (2013), and P 0 . In particular it would be interesting to consider the effects of adding the obvious back pressure to the existing policy P 0 , perhaps following Le et al (2013).…”

Continuous and Discrete-Time Optimal Controls for an Isolated Signalized Intersection

“…In the research done by Varaiya [11] and Le et al [12], the study of pressure-based signal control developed stability properties of a decentralized signal timing policy for networks with stochastic arrivals.…”