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. 05, 2011
Filed:
Dec. 18, 2009
Hajime Hamada, Kawasaki, JP;
Hiroyoshi Ishikawa, Kawasaki, JP;
Yuichi Utsunomiya, Kawasaki, JP;
Kazuo Nagatani, Kawasaki, JP;
Nobukazu Fudaba, Kawasaki, JP;
Shohei Ishikawa, Kawasaki, JP;
Hajime Hamada, Kawasaki, JP;
Hiroyoshi Ishikawa, Kawasaki, JP;
Yuichi Utsunomiya, Kawasaki, JP;
Kazuo Nagatani, Kawasaki, JP;
Nobukazu Fudaba, Kawasaki, JP;
Shohei Ishikawa, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A predistortion apparatus for compensating for a distortion arising from a non linear property in input to output characteristics of an amplifier, by processing calculation of a plurality of coefficients for a plurality of power series defining the predistortion characteristics for a plurality of power ranges, respectively, the predistortion apparatus includes: a coefficient update unit for setting and updating coefficients of the power series to provide the predistortion characteristics for the plurality of power ranges in accordance with a comparison between the input and output of the amplifier; and a determination unit for determining at least one threshold value defining the plurality of power ranges by shifting the threshold value and operating the coefficient update unit for updating the coefficients for each of the power series corresponding to each of the power ranges defined by the shifted threshold value.