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:
Jun. 30, 1998
Filed:
Mar. 13, 1997
Sen W Chu, Torrance, CA (US);
Milos D Ercegovac, Los Angeles, CA (US);
Kenneth A Essenwanger, Walnut, CA (US);
Tomas Lang, Irvine, CA (US);
Allen L Sakai, Laguna Niguel, CA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A digital phase to digital sine and cosine amplitude translator generates sine and cosine outputs from an input angle word, which is decomposed into the most significant bits (MSBs) and the least significant bits (LSBs), and the octant number of the angle is identified by the octant identifier bits. Radix-4 multiplier/adder circuits improve the efficiency of multiplication/addition computations. An incrementor and a decrementor are used for sine and cosine MSB computations, respectively, to further save the computer memory and logic. In a preferred embodiment, the MSBs of the sine and cosine outputs for all octants are generated based upon the octant number of the input angle, and the LSBs of the outputs are generated by trigonometric approximations and octant selection, thereby resulting in a savings in computer memory and logic.