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:
Feb. 25, 2003
Filed:
Feb. 15, 2001
Yasuhiro Wake, Tokyo, JP;
Taisuke Sasada, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
Signals from microphones are first stored in memory circuits and then supplied to a cross-correlation arithmetic circuit following which a cross-correlation operation is carried out and cross-correlation function values are calculated for each time difference. An evaluation function circuit carries out addition processing of particular time intervals based on the cross-correlation function values and then searches for the maximum value to calculate time differences. Signals from the microphones are first stored in memory circuits and then supplied to a cross-correlation arithmetic circuit following which a cross-correlation operation is carried out and cross-correlation function values are calculated for each time difference. An evaluation function circuit carries out addition processing of particular time intervals based on the cross-correlation function values and then searches for the maximum value to calculate time differences. A position calculation circuit finds a horizontal direction angle and a vertical direction angle based on these time differences (delay).