G PHYSICS
G08 SIGNALLING
G08G TRAFFIC CONTROL SYSTEMS
G08G1/00 Traffic control systems for road vehicles
G08G1/123 indicating the position of vehicles, e.g. scheduled vehicles;; Managing passenger vehicles circulating according to a fixed timetable, e.g. buses, trains, trams
G08G1/127 to a central station; ; Indicators in a central station