Title:
DEVICE AND METHOD FOR PRODUCING HIGH QUALITY AUDIO BEAM
Document Type and Number:
Japanese Patent JP2005304028
Kind Code:
A
Abstract:
To reduce THD, and to equalize frequency characteristics.
A system for modulating an ultrasonic wave carrier beam using an audio input signal is proposed. An audio signal is divided into frequency bands, and each frequency of these different bands is to be treated individually. Concretely, different modulation methods are to be used corresponding to respective divided frequency bands. And each aperture size of different converters is to be used in relation to each different frequency signal. A frequency equalizer is further provided within each frequency band. Finally, a relatively small amplitude modulation degree (one or a plurality of indexes) is to be used in response to a signal in a low frequency band.
Inventors:
SUN XIAOBING
OKADA KANZO
OKADA KANZO
Application Number:
JP2005110183A
Publication Date:
October 27, 2005
Filing Date:
April 06, 2005
Export Citation:
Assignee:
SONY CORP
International Classes:
H04R1/40; H04R3/00; H04R3/14; H04R1/26; H04R3/04; H04R17/00; (IPC1-7): H04R3/00; H04R1/40
Attorney, Agent or Firm:
Akira Koike
Eiichi Tamura
Seiji Iga
Eiichi Tamura
Seiji Iga
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