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:
Mar. 23, 2010
Filed:
Mar. 21, 2008
Hidefumi Suzaki, Shiga, JP;
Junji Ito, Osaka, JP;
Fumiya Kamimura, Osaka, JP;
Shigeki Nakamura, Osaka, JP;
Hidefumi Suzaki, Shiga, JP;
Junji Ito, Osaka, JP;
Fumiya Kamimura, Osaka, JP;
Shigeki Nakamura, Osaka, JP;
Panasonic Corporation, Osaka, JP;
Abstract
A differential amplifier circuit is connected to the input node and the output node of the final amplification stage through detection circuits. The signal level difference output from the differential amplifier circuit does not change even if the input power varies. Because a change in the power gain at the output node does not travel back to the input node when the load impedance of the wireless frequency power amplifier varies, it is possible to detect only the change in the load impedance. Damage to the final stage can be prevented by controlling the operating current of the final stage and the gain of the drive stage according to the detected load variation. Nonlinear distortion in the wireless frequency power amplifier output can also be reduced by detecting and canceling the change in the gain of the drive stage by changing the gain of the adjustment stage.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile