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:
Sep. 03, 1991
Filed:
Jun. 01, 1989
Douglas E Mandell, Sausalito, CA (US);
Craig C Todd, Mill Valley, CA (US);
Roger Dressler, Martinez, CA (US);
Dolby Laboratories Licensing Corporation, San Francisco, CA (US);
Abstract
The decoder of this invention decodes at least two channel signals in a directional information system where one or more input signals containing directional information have been encoded into the two or more channel signals. The decoder generates a first control signal substantially proportional to the logarithm of the ratio of the amplitudes of two of the channel signals to detect, as between two of the channel signals, whether the amplitude of one signal dominates that of the other. The decoder also generates a second control signal substantially proportional to the logarithm of the ratio of the amplitudes of the sum and the difference between two of the channel signals to detect the dominant signal in terms of amplitude. The decoder includes a matrix means responsive to the two or more channel signals and the two control signals for generating a number of output signals according to an algorithm. The control signals generated are used to steer the directional information systems in such manner through the matrix means that the directional effects of the output signals are enhanced. The matrix means generates three directional control signals from the two control signals.