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. 13, 2004
Filed:
Dec. 20, 2002
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
Provided is a distortion-compensated amplifying circuit capable of suppressing distortion without attenuating a level of carrier components, and further obtaining a larger amount of suppression of distortion, which has not been achievable by conventional distortion-compensated amplifying circuit using a pre-distortion technique. A balanced type amplifying circuit is structured such that amplifiers and placed in parallel are sandwiched by 90-degree hybrid circuits and . The 90-degree hybrid circuit is supplied with an original signal including carrier components and a distortion signal including distortion equal in amplitude and opposite in phase (having a phase difference of 180 degrees) to distortion that occurs when the original signal is amplified by the amplifiers and . The 90-degree hybrid circuit performs a process of differential amplification with a phase difference of 180 degrees between the original signal and the distortion signal. Then, the amplified original signal and distortion signal outputted from the 90-degree hybrid circuit are combined by a directional coupler , thereby canceling distortion components included in both signals with each other.