实时估算交叉口排队长度一直以来都是一个挑战性的问题.当信号交叉口没有配备固定交通流检测器时,问题将变得更加复杂.本文中,我们研究利用车辆GPS数据估算交叉口实时排队长度的关键技术,建立了基于交通波理论的信号交叉口实时排队长度估算模型,并首次引入了"消散延误"的概念.利用实时排队长度估算模型与车辆的"消散延误"数据,可以实现交叉口每一个信号周期的排队长度的实时估算.本文对模型和算法进行了实地测试,测试结果表明,本文建立的模型和算法可以较为准确地估算信号交叉口的实时排队长度.
To estimate time-dependent queue length problem at signalized intersection is a challenging task for a long time, which will be more difficult if fixed-location sensors are unavailable at these intersections. In this paper, it is studied that the key technologies on how to use GPS data to estimate real time queue lengths at signalized intersections. A real time queue length estimation model is presented based on traffic shockwave theory and the concept of "discharging delay" is first put forward. Utilizing the real time estimation model and the "discharging delays" data of a few queuing vehicles, it can be computed that realtime queue length estimations cycle-by-cycle. In the end the model and algorithm is tested in a real intersection of Guangzhou city. The testing results show that the proposed model and algorithm can estimate queue lengths with satisfactory accuracy.