Disclosed is a feature for a vehicle that enables taking precautionary actions in response to conditions on the road network around or ahead of the vehicle, in particular, a curved portion of a road with insufficient superelevation. A system for detecting such waves includes a device having a first magnetic layer having a fixed magnetization direction, a second magnetic layer having an unfixed magnetization direction responsive to the electromagnetic wave, and a barrier layer positioned between the first and second magnetic layers. The two attaching portions are configured to have a height different from that of the base portion and are attached to the housing. When the sniffer finds a match, the computer terminal user may be asked if assistance is needed or the user may be automatically referred to the help desk. The transmitter is connected to the encoderdecoder apparatus and to the antenna through the duplexer.