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:
Apr. 12, 1988
Filed:
Dec. 06, 1985
Tim A Williams, Austin, TX (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A method which reduces the memory required to store correction factors used in logarithmic addition and subtraction of logarithmic operands. The method is implemented by a circuit which adds a predetermined correction factor to the minimum value of two logarithmic input operands. Correction factors are quantized to single polarity values. Predetermined ranges of magnitude values of the correction factors are selected in which the minimum value of each range is represented by a bias level. As a result of the bias levels, stored representations for the addition and subtraction factors are made much smaller resulting in less memory which is required. An addition of a predetermined bias level to the minimum value is effected simultaneous to addressing a predetermined adjustment factor in the reduced memory. A second addition is required to provide an output which represents either an addition or subtraction of the signed operands.