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. 22, 2000
Filed:
Jul. 08, 1996
William Spencer Worley, III, Half Moon Bay, CA (US);
Silicon Wireless Limited, Mountain View, CA (US);
Abstract
Signal processing to remove unwanted signal components of non-linear elements such as RF amplifiers in broadband wireless communications systems that exhibit unwanted intermodulation products. An information signal is processed to form a processed output signal, V.sub.od. A signal preprocessor includes a base modulator for modulating the information signal to form base modulated signals, a band modulator for modulating the base modulated signals to form an input signal, V.sub.i, a distortion processor for providing a predistortion signal V.sub.pd having selected predistortion terms of the Taylor series form [k.sub.1,(V.sub.i).sup.1, k.sub.2 (V.sub.i).sup.2, k.sub.3 (V.sub.i).sup.3, . . . ], and a broadband processor for combining the input signal V.sub.i and the predistortion signal V.sub.pd to form a predistorted signal V.sub.id with the selected predistortion terms of the Taylor series form [k.sub.1 (V.sub.i).sup.1, k.sub.2 (V.sub.i).sup.2, k.sub.3 (V.sub.i).sup.3, . . . ] having reduced amplitude. A non-linear element having a non-linear transfer function for processes the predistorted signal V.sub.id to form the output signal with the selected predistortion terms of the Taylor series form [k.sub.1 (V.sub.i).sup.1, k.sub.2 (V.sub.i).sup.2, k.sub.3 (V.sub.i).sup.3, . . . ] having reduced amplitude. Amplifiers achieve substantial improvements in efficiency, an increase of 40-80% of usable power, due to the reduction of intermodulation products. In particular, the third order products are reduced.