| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a positional information system capable of providing accurate positional information at any installation location by using acoustic to transmit the positional information at a location where a user wants to detect a position thereof or at each location. <P>SOLUTION: The present invention comprises: a positional information transmission device which emits an audio signal, modulated by positional information indicating a specific location, at the specific location and to a neighborhood thereof; and a portable terminal device, a device carried by a user, which has a demodulation section to receive the audio signal emitted by the transmission device and to demodulate the positional information from the received audio signal and a notification section to notify the user of a current position based on the demodulated positional information. <P>COPYRIGHT: (C)2013,JPO&INPIT |
