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:
Oct. 03, 2006
Filed:
Oct. 23, 2003
Mitsuru Tanabe, Katano, JP;
Takaharu Saeki, Kyoto, JP;
Yoshihisa Minami, Otsu, JP;
Koichiro Tanaka, Takarazuka, JP;
Noriaki Saito, Machida, JP;
Mitsuru Tanabe, Katano, JP;
Takaharu Saeki, Kyoto, JP;
Yoshihisa Minami, Otsu, JP;
Koichiro Tanaka, Takarazuka, JP;
Noriaki Saito, Machida, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The present invention provides a transmitter conforming to the EER method in a wide frequency band at high efficiency. For this purpose, the amplitude component of a modulated signal is input to the power supply terminal of a high-frequency power amplifier, the I and Q quadrature signals thereof are input to the high-frequency input terminal of the high-frequency power amplifier, and the original modulated signal is obtained from the output of the high-frequency power amplifier. A collector voltage is supplied from DC—DC converter grouphaving output voltages being different sequentially to an emitter followervia a switch group. One of the outputs of the DC—DC converterstois selected depending on the level of the amplitude component as the collector voltage and supplied to the emitter follower, whereby the difference between the emitter voltage of he emitter followerand the collector voltage of the emitter followeris made smaller and the efficiency of the emitter followeris raised; furthermore, the power supply voltage of the high-frequency power amplifieris voltage-converted by the emitter follower, whereby operation in a wide frequency band is made possible.