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:
Aug. 19, 2003
Filed:
Nov. 30, 2000
Jonathan E. Greene, Great Barrington, MA (US);
Mercury Computer Systems, Inc., Chelmsford, MA (US);
Abstract
A system for calculating fast Fourier transforms includes a non-final stage calculating means for repetitively performing in-place butterfly calculations for n−1 stages as well as a final stage calculating means for performing a final stage of butterfly calculations. The final stage calculating means includes a first loop and a second loop. The first loop performs a portion of the final stage butterfly calculations by iterating on a table of first loop index values consisting of values that bit-reverse into themselves. The first loop also includes control logic to select inputs for groups of butterfly calculations based on the first loop index values. The second loop performs a remaining portion of the final stage butterfly calculations by iterating on a table of second loop index value pairs consisting of two values that bit-reverse into each other. The second loop includes control logic to select inputs for two groups of butterfly calculations based on the two second loop index pair values respectively.