Apparatus and method for the survey of the radio listener or the television viewer

摘要

PURPOSE: To provide a survey (investigation) method in which a composite signal composed of a programming signal and a survey signals is transmitted and the programming and survey signals are acoustically reproduced from a loudspeaker within an audible range. ;CONSTITUTION: A survey signal is uniquely coded for identifying a signal source, such as the radio station, television channel, etc. On the reception side, the acoustic survey signal is controlled so that the signal may become inaudible at a sufficient distance from a loudspeaker 16 and converted into a nonacoustic signal. The converted nonacoustic signal is transmitted and detected by means of a portable unit 26 worn by a person to monitor the listening and/or viewing habit of the person. When the unit 26 detects the converted survey signal, the signal source tuned by the person is discriminated. This conversion prevents the person to be monitored from getting confused by the acoustic survey signal.;COPYRIGHT: (C)1996,JPO