A system for detecting customer media comprising an RF transceiver in a public transport conveyance, where the system for each passenger compartment or car includes a number of reading devices, which are interconnected and connected to computer serving as an on-board unit for the purpose of data communication, wherein the entire interior of passenger compartment or car is covered by a number of reading devices, where the reading devices are arranged in such a manner that any two reading devices are provided on opposite lateral walls of the passenger compartment or car, which cover the room up to the opposite wall, or that each two reading units are arranged in the roof area or floor area symmetrically around the longitudinal axis of the passenger compartment or vehicle, where the detection range of the respective two reading devices is substantially identical and substantially covers the entire width of the passenger compartment or car in the floor area or roof area, where the floor area or the roof area is covered considered axially along a pre-specified length.