Module 2 : Traffic Measurement Procedures
Lecture 11 : Travel Time Data Collection
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Automatic Vehicle Identification (AVI) - Probe vehicles are equipped with electronic tags. These tags communicate with roadside transceivers to identify unique vehicles shown in Fig. 1 and collect travel times between transceivers [16].
Figure 1: AVI Vehicle-to-Roadside Communication Process, Source: Travel Time Detection Hand Book, [16]
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Ground-Based Radio Navigation - It is used for transit or commercial fleet management, this system is similar to the global positioning system (GPS). Data are collected by communication between probe vehicles and a radio tower infrastructure as shown in Fig. 2 [16].
Figure 2: Ground-Based Radio Navigation Communication Process, Source: Travel Time Detection Hand Book, [16]
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