Transit Signal Priority (TSP) has been studied as a control strategy that offers preferences to transit vehicles at signalized intersections. While TSP has been deployed in many places, several shortcomings such as adverse effect on side streets and uncertainty of benefit have been identified. Therefore, a new Transit Signal Priority (TSP) logic is proposed to overcome these shortcomings, taking advantage of the resources provided by Connected Vehicle (CV) technology, including two-way communications between the bus and the traffic signal controller, accurate bus location detection and prediction and the number of passengers. The key feature of the proposed TSP logic is green time re-allocation, which moves green time instead of adding extra green time. The TSP is also designed to be conditional. That is, delay per person is used as the most important criterion deciding whether TSP is to be granted. The logic developed in this research is evaluated in two ways: with analytical and microscopic simulation approaches. In each evaluation, the proposed TSP is compared against two scenarios: no TSP and conventional TSP. The measures of effectiveness used are bus delay and per person delay of all travelers. Simulation-based evaluation results show that the proposed TSP logic reduces bus delay between 9% and 84% compared to conventional TSP and between 36% and 88% compared to the no TSP condition. The range of improvement corresponding to the four different v/c ratios is tested, which are 0.5, 0.7, 0.9 and 1.0. No significant negative effects are caused by the proposed TSP logic.
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