The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 10, 2000
Filed:
Sep. 16, 1997
Mariko Aoki, Yokohama, JP;
Shigeaki Aoki, Yokosuka, JP;
Hiroyuki Matsui, Yokohama, JP;
Yutaka Nishino, Miura, JP;
Manabu Okamoto, Yokohama, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
Abstract
A time difference .DELTA..tau. between the arrival of acoustic signals from sound sources to microphones 1, 2 is detected from output channel signals L, R from microphones 1, 2. By Fourier transform, the signals L, R are divided into respective frequency bands L(f1)-L(fn), R(f1)-R(fn). Differences .DELTA..tau.i (i=1, 2, . . . n) in the time-of-arrival of L(f1)-L(fn) and R(f1)-R(fn) to the microphones 1, 2 as well as a signal level difference .DELTA.Li are detected. L(f1)-L(fn), R(f1)-R(fn) are divided into a low range of fi<1/(2 .DELTA..tau.), a middle range of 1/(2 .DELTA..tau.) <fi<1/.DELTA..tau., and a high range of fi>1/.DELTA..tau.. Utilizing .DELTA..tau.i for the low range, .DELTA.Li and .DELTA..tau.i for the middle range and .DELTA.Li for the high range, a determination is made from which sound source L(fi), R(fi) are oncoming to deliver outputs separately for each sound source. The outputs are subject to an inverse Fourier transform for synthesis separately for each sound source.