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:
Jan. 30, 2007
Filed:
Dec. 09, 2003
Yasunori Suzuki, Yokohama, JP;
Shinji Mizuta, Yokohama, JP;
Tetsuo Hirota, Kanazawa, JP;
Yasushi Yamao, Yokosuka, JP;
Yasunori Suzuki, Yokohama, JP;
Shinji Mizuta, Yokohama, JP;
Tetsuo Hirota, Kanazawa, JP;
Yasushi Yamao, Yokosuka, JP;
NTT DoCoMo, Inc., Tokyo, JP;
Abstract
A combined signal of a digital pilot signal and a digital transmission signal is applied to a digital predistorter (), wherein it is added with odd-order distortions based on a power series model to generate a predistorted signal, then the predistorted signal is converted by a DA converter () to an analog signal, then the analog signal is upconverted by a frequency upconverting part () to a send frequency band, and the upconverted signal is output after being amplified by a power amplifier (). A pilot signal component is extracted from the power amplifier output, then odd-order distortion components of the power series model are extracted by a digital predistorter control part () from the pilot signal component, and the odd-order distortions in the digital predistorter () are controlled to decrease the levels of the distortion components.