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:
May. 31, 1988
Filed:
Aug. 14, 1985
Israel B Zibman, Newton, MA (US);
Nigel P Morgan, Belmont, MA (US);
GTE Laboratories Incorporated, Waltham, MA (US);
Abstract
A fast Fourier transform is performed under control of stretched out microcode. Sequential data inputs are multiplied by coefficients addressed by microcode in a digital multiplier. The resultant products are sequentially stored in three registers. The product stored in the second register is applied as one input to an arithmetic logic unit and the product stored in either the first or the third register is applied as the second input to the logic unit in order to compute the operation pairs (ax.+-. by). The Fourier transform is based on Winograd Fourier transforms modified for only real inputs and to force operations into the form (ax.+-. by). Sample points are initially scaled using the same circuit by performing an OR operation with respect to each sample point and an accumulated OR taken from the output of the ALU. The position of the most significant one bit in the final accumulated OR is indicative of the required scale factor. That scale factor is applied to the multiplier to scale each sample point.