| 摘要 |
<p>PROBLEM TO BE SOLVED: To perform acoustic communication with a particular device within a range where an acoustic signal reaches using the acoustic signal.SOLUTION: Acoustic signal generation means 101 generates an acoustic signal in which information is superposed on a particular frequency component. Storage means 102 stores data associating a ratio between before and after frequency shift of the acoustic signal with data representing moving speed as data on a frequency at which the acoustic signal is shifted. When the acoustic signal generation means 101 generates an acoustic signal, shifting means 103 shifts the frequency of the acoustic signal, i.e. the acoustic signal in which information is superposed on the particular frequency component, according to shift frequency data stored in the storage means 102. Output means 104 outputs the supplied acoustic signal, i.e. the acoustic signal whose frequency is shifted by the shifting means 103.</p> |
