Title:
変調装置、復調装置、情報通信システム及びプログラム
Document Type and Number:
Japanese Patent JP5292893
Kind Code:
B2
Abstract:
To exchange information without disturbing listening of sound.
A modulation apparatus generates a waveform obtained by combining a plurality of frequency components. When superimposing information on the waveform, the modulation apparatus changes factors (frequency values or levels) of respective frequency components in accordance with encoded information. In a case where there are a waveform represented by combining frequencies f0, f1, f2and f3, for example, when superimposing a code stream "101", the modulation apparatus shifts the frequency f1just by Δ1, shifts the frequency f2just by Δ0and shifts the frequency f3just by Δ1. Namely, when a case where no shift is performed is defined as a criterion (a), the modulation apparatus combines waveforms of frequency components obtained by shifting respective frequencies from a criterion value just by values corresponding to the code stream (b).
COPYRIGHT: (C)2010,JPO&INPIT
Inventors:
River Hara Takehiko
Application Number:
JP2008092493A
Publication Date:
September 18, 2013
Filing Date:
March 31, 2008
Assignee:
Yamaha Corporation
International Classes:
H04B11/00; G10L19/018
Domestic Patent References:
| JP2003517742A | | | | |
| JP2008005541A | | | | |
| JP2007013925A | | | | |
Attorney, Agent or Firm:
Asahi Patent Office
